KIGALI SUSTAINABILITY METRICS EXPLORING PERFORMATIVE APPROACHES TO URBANISM
CArnegIe mellon unIverSITy mASTerS of urBAn deSIgn | Summer 2012
Table of Contents A Introduction A1 Studio Description A2 Approach A3 Research Trip B B1 B1.1 B1.2 B1.3 B1.4
Kigali Planning context Summary of Planning to Date Kigali Conceptual Master Plan: 2007 Nyarugenge District Plan Nyarugenge Zoning Code Housing Market Study
C Sustainability metrics for Kigali C1 Existing Sustainability Metrics C2 Transforming Existing Planning Objectives into Sustainability Metrics C3 Principles, Objectives and Conceptual Metrics C4 Primary Metrics Influencing Neighborhood Form D D1 D1.1 D1.2 D1.3 D2
Testing the Metrics Study Area Overview Location and Existing Conditions Planning to Date Opportunities and Constraints Approach & Methodology
D3 Testing the Existing Zoning D3.1 Site Selection D3.2 Zoning Massing and Implied Typology Study D3.3 Zoning Evaluation D3.4 Current Zoning Summary D3.5 Urban Sustainability Assessment D4 Urban Design Scenarios D5 District Level Decision Making D5.1 Primary Metrics Influencing Neighborhood Form - District Scale D5.2 Scenario Comparison by Key Metric D5.3 Scenario Framework Comparison D6 Block Level Decision Making D6.1 Primary Metrics Influencing Neighborhood Form - Block Scale D6.2 Block Level Massing Comparison D6.3 Metric Impacts at the Block Scale D7 Street Level Decision Making D7.1 Primary Metrics Influencing Neighborhood Form - Street/Parcel Scale D7.2 Zoning Category Comparison by Metric D7.3 Street Level Visualization Comparison E Conclusion and next steps E1 Conclusions E2 Analysis and Recommendations F F1 F2
Appendix Sustainability Metrics for Kigali Kigali Climate Analysis
Project Team Studio Professor Master of Urban Design Students
Studio Critics
Jonathan Kline Jison Nam Varsha Padmanabhan Elia Sorice Meng Zhang Don Carter Stephen Quick Stefani Danes Rami el Samahy Kelly Hutzell Steve Lee
Acknowledgements City of Kigali
Liliane Mupende Donna Rubinoff Joshua Ashimwe Enrico Moriello (Surbana)
Kigali Institute of Science & Technology
Killian Doherty Garret Gantner Ilaria Boniburini TomĂ Berlanda
Carnegie Mellon Rwanda
Bruce Krogh Margie Krogh Michel Bezy Crystal Rugege
Architecture for Humanity
Kevin Gannon
The 2012 Sustainable Urbanism Studio would like to thank the following individuals for their assistance, knowledge and insight during our travels and study. We are especially thankful to the planning staff and consultants of the City of Kigali for allowing us to work with them, and for generously sharing information and ideas and feedback to support our effort. In particular we want to thank Donna Rubinoff for her dedication to the studio and the many hours she spent critiquing the work by teleconference upon our return to Pittsburgh. It is our hope that the work of studio is of value as the actual planning and implementation moves forward. We are also deeply indebted to the faculty of KIST for allowing us to visit their studios and help orient us to Kigali and the issues the city faces. A special thanks to Killian Doherty who went out of his way to host us, orient us to the city, and point us towards progressive approaches to architecture in Africa. Finally our trip would never have gotten off the ground without the essential assistance from the faculty and staff at CMU Rwanda who help make all of our arrangements and spent time helping us understand Kigali and Rwanda. Lastly a thank you to Kevin Gannon who provided key insights into contemporary architecture and urbanism in Africa.
Jonathan Kline Studio Professor
A
introduction
A1
Studio Description
A2 Approach A3 Research Trip
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A introduction A1 Studio Description 48-708 Sustainable Urbanism Studio The Carnegie Mellon University Master of Urban Design (MUD) program is a post-professional degree, intended to prepare graduates for careers using design to critically address environmental, economic, social and cultural issues affecting the contemporary metropolis. The studio-based curriculum allows students to explore strategies for development in a variety of scales and settings, including the post-industrial city, the suburban periphery, and the rapidly urbanizing region. This intensive 12-month program is open to recent graduates and practicing professionals with a previous bachelor degree in architecture, landscape architecture, or city planning.
Working in partnership with the Urban planning and Land Management Unit of the City of Kigali, the studio made recommendations for sustainable development by simulating the effects of the new zoning code on future development and then benchmarking these scenarios against a set of urban sustainability metrics. The studio built on the goals and parameters laid out in the City of Kigali Conceptual Master Plan and the Detailed Master Plan for the Nyarugenge District by interpreting and quantifying their recommendations for sustainability and then testing a series of urban design scenarios to examine how these goals could be met.
The final studio course in the program, Sustainable Urbanism, explores urban design in a rapidly growing urban region and includes a study tour to explore and document the chosen city of study, collect information and meet with local partners. The Sustainable Urbanism Studio investigates how aspects of urban sustainability can be integrated into the urban morphology and regulation of a growing urban district. The studio explores both formal, and performative characteristics of urban development and makes recommendations for how the chosen study area can evolve into a sustainable 21st century city. The product of the studio is a report documenting the design exploration of the district including recommendations for urban regulation.
Urban design scenarios were generated for parts of the Rwezamenyo, Gitega and a small section of the Nyarugenge sectors in the Nyarugenge District. This area is currently a mix of formal and informal existing development. Today the area is primarily residential, but also includes small commercial uses, along with a public market and other institutional uses. The area is close to both the Kigali central business district and the Kigali Institute for Science and Technology.
For the summer of 2012 the studio focused on the City of Kigali in Rwanda, building on the ambitious and forward thinking planning work for Kigali an emerging hub in East Africa. Using recent planning work as a basis for exploration, the studio developed and tested a set of possible urban sustainability metrics for Kigali.
int roduct ion
The studio generated urban design scenarios for this area at a range of scales using the recently completed sub Kigali City Sub-Area Plan and Zoning and Urban Design Guidelines to define land use and zoning parameters. These scenarios were used to understand the current regulatory tools in place and the urban form they imply; and to understand which aspects of urban sustainability the existing tools support and where opportunities exist to improve their performance. Finally, as an illustration of the possible expansion of planning tools and regulatory mechanisms, the studio generated a series of design scenarios that apply an expanded set of urban sustainability regulatory metrics. These illustrate how an expanded set of tools could help shape a more sustainable future for the city.
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Studio process
Kigali research trip and site visits | Testing urban design scenarios based on the new zoning with a physical model Generating sustainability metrics for Kigali | Teleconference with Kigali planning officials k iga li s u s ta in a b ility Me tr ic s
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A InTroduCTIon A2 APProACh exPlorIng SuSTAInABIlITy AS A drIver for urBAn deSIgn Unlike many academic and professional urban design efforts, the goal of this project was not to generate a specifi c master plan or singular set of proposals for a piece of the city. Instead the studio focused on designing how the city is regulated and how principles for sustainability can be integrated into the rules of a city. The overarching goal of the study is to explore how sustainability can be measured and regulated at the urban scale using performative metrics, and how these in turn can shape the form of the city in both traditional and novel ways. In this case the studio focused on Kigali, the rapidly growing capital of Rwanda. Kigali has an ambitious master plan, a new zoning code and a desire to modernize the city as part of larger economic modernization project for the country. The city is changing fast and major decisions for its future are underway. The hope is that a performance based approach can help inform diffi cult redevelopment choices such as deciding which areas of the city to completely redevelop and which to allow to evolve, where and how new infrastructure should be built, and how principles of sustainability can be designed into the city’s regulatory tools. The study only scratches the surface of how a comprehensive approach to sustainability might be implemented in Kigali. It focused on a single piece of the city with a mix of existing formal and informal development and used the current planning vision and the recently developed zoning code as basis for generating a variety of likely development scenarios. These scenarios were then compared to a series of ideal sustainability performance metrics. Using this process, the performance of the current regulatory structure was tested for sustainable outcomes. Through this process the studio made a series of specifi c recommendations about the specifi c zoning districts examined, as well as broader approaches to integrating sustainability into planning and development decision making. Kigali provided a rich and incredibly challenging context for this type of exercise. It is our hope that the work of the studio can help inform the future of Kigali.
Jonathan Kline Studio Professor
InT roduCT Ion
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SCAleS & TeChnIqueS
Physical model testing urban massing implications of zoning | Infrastructure scenarios Urban massing scenarios | Street level development scenarios K IgA lI S u S TA In A B IlITy me Tr IC S
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A introduction A3 Research trip May & June 2012 The studio traveled to Rwanda in May and June of 2012 for ten days, spending the majority of the trip in Kigali, with a side trip north to the Volcanoes National Park and Lake Kivu. In Kigali students visited the Urban planning and Land Management Unit of the City of Kigali, the architecture studios of the Kigali Institute of Science and Technology, and the emerging Carnegie Mellon Rwanda campus. The majority of the time in Kigali was spent walking the city, particularly the parts of the Nyarugenge District that the studio focuses on. The short trip to the north allowed the group to get a sense of the broader countryside, culture and landscape, and to experience the amazing wildlife of the Virunga mountains.
Students in Downtown Kigali | Approaching Kigali from the north New infrastructure in a redevelopment area | CMU Rwanda campus Mountain gorillas | Bicycle taxi on the road int roduct ion
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Research trip
Downtown Kigali | Downtown Kigali | Recent development in Kigali Informal housing in Nyarugenge | New community center designed by Killian Doherty| Informal housing in Nyarugenge Architecture studios - KIST | Metal working shop | Students in the Virungas k iga li s u s ta in a b ility Me tr ic s
B
kigali planning context
B1 Summary of Planning to Date B1.1 Kigali Conceptual Master plan:2007 B1.2 Nyarugenge District Plan B1.3 Nyarugenge Zoning Code B1.4 Housing Market Study
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B Kigali Planning Context B1 Summary of planning to date B1.1 Kigali Conceptual Masterplan: 2007 Following the completion of the Existing Conditions Analysis, the Kigali Conceptual Master Plan is the second step in developing a comprehensive plan for the City. The Kigali Conceptual Masterplan which provides a long range vision for the city, served as the key foundation for this study. By adopting the Vision 2020 Plan, leaders of Rwanda envision Rwanda to be a model of prosperity, environmental sustainability, and social harmony. A key component of the KCMP is the transect model which illustrates how future aspects of urbanization such as buildings, infrastructure and density should respond to topography and each other. The Kigali transect model is an interpretation of the Smart Code, a city-scale regulatory mechanism to control both urban form and density. Given the unique topographic conditions of the city and the current urban fabric, the transect model has the potential to serve an effective site-specific tool to transition Kigali into a modern city reflecting the goals of Vision 2020.
Kigali Conceptual Master Plan
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The Transect Model
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B1.2 nyArugenge dISTrICT PlAn The 2010 Nyarugenge District Plan & Zoning project, which translates vision into implementation plans, is another key document that became the springboard for the study. Kigali CBD is divided into three planning areas, Muhima, Nyarugenge and Kimicanga. Muhima is the modern CBD core of Kigali. Nyarugenge is the Historic CBD of Kigali and Kimicanga is classifi ed as the entertainment district. The District Plan has taken into consideration the KCMP as well as the needs of the current urban fabric. The City envisions the current Nyarugenge Central Business District to be a vibrant commercial neighborhood. The master plan for the Kigali CBD focuses on creating short, medium and a long term physical development for the city with attractive commercial, and offi ce spaces in the CBD.The Nyarugenge plan also aims at creating zones of varied residential and a mix of uses. The objective at the district scale ensures conserving the natural assets as well as creating a sustainable living environment. The key concepts that have driven the district are redevelopment of the existing city and densifi cation of the commercial districts. The plan also focuses on revitalizing the good housing area in Kiyovu and redeveloping the rest of the housing fabric. Nyarugenge District has been planned to retain its historic, low-rise medium density character. With new development focused on creating a mix of uses. While the Nyarugenge market is proposed to be relocated. The remaining organic market areas are planned to be retained and developed for tourism.
Nyarugenge District Proposed Zoning Plan 2020
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B KIgAlI PlAnnIng ConTexT B1 SummAry of PlAnnIng To dATe B1.3 nyArugenge ZonIng Code Developed in 2010, the Nyarugenge District zoning code provides strong density and land use control, and generally coincide with existing land uses. Main zoning categories include commercial, industrial and open spaces. The residential areas are further classifi ed into single family residential R1, mixed single family R1A, rural R1B, low rise R2 , medium rise R3 and high rise R4. The commercial areas are classifi ed as mixed use C1, neighborhood level commercial districts C2, city level C3, C3A, C3B, C3C, regional commercial districts C4, C4A and retail warehouse district C5. • Each residential zone prescribes specifi c housing types such as attached and detached villas, multifamily housing and workers accommodation. • Commercial zones are classifi ed broadly with a mix of uses. It contains retail, laundry, shops, restaurants, offi ces, showrooms, entertainment arcades, cinema, hotel, service apartment’s petrol station and recreational activities. There are certain conditional uses for housing in this category too. • Public facilities are classifi ed into kindergarten and childcare, primary and secondary schools, hospitals and health institutions, medical centers, religious Institutions, government offi ces, public libraries, museums, galleries, sports facilities, rapid transit stations and convention centers. • Open space areas are categorized as public parks, golf courses, private parks and wildlife zones. Nyarugenge zoning map
KIgAl I Pl AnnIng ConT exT
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Summary of major planning documents
KCMP
Nyarugenge District Plan
Zoning Code
Scale
City
Type of
City level decisions adhering to the Vision 2020
Decisions
Drivers of Economy, Equity and Environment.
Level of
Overarching vision that addresses topography and land use through the transect model.
Detail
District
Zone
District Level plans pertaining to the districts of Nyarugenge, Muhima and Gasabo.
Zoning based on land use with differentiation of residential, commercial, public spaces, parks and open spaces
Natural preserves, topography and infrastructure planning Details of infrastructure, transportation, city planning, environmental conservation and preservation.
Urban revitalization specific to the block and parcel.
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B Kigali Planning Context B1.4 Summary of planning to date Housing Market Study Analysis Rwanda has one of the lowest rates of urbanization in Sub-Saharan Africa, however, it is one of the most densely populated nations. Current rates are 19% as compared to 42% in other African countries, and urbanization is expected to reach over 50% by 2050. Population growth and internal migration to Kigali will strain existing infrastructure and the housing markets as the population is projected to grow by 1 million by 2025. This has major implications for urban policy in order to address growing demands within Kigali City and the surrounding areas.
Housing Stock The cost of housing is high relative to the available housing stock. As a result, more than 80% of Kigali’s population lives in informal settlements. These informal settlements occupy 62% of the land area in the city.
Infrastructure Most homes in Kigali have electricity and water, however, sanitation is largely inadequate—there is no piped sewage in the city. Formal houses usually have indoor toilets connected to septic tanks, while informal settlements typically have pit latrines that are either not maintained or emptied into the wetlands. Sewage treatment plants are mandated for new developments exceeding 50 people.
Housing Market Constraints There are several factors attributed to housing supply and finance that contribute to the affordability gap in Kigali City.
High cost of on-site infrastructure: The steep terrain and size of single family homes makes the provision of on-site infrastructure difficult. This includes roads, sewage treatment, landscaping, and street lights. As larger plots are acquired and consolidated, the cost of on-stire infrastructure increases. • Limited capacity of developers: Most developers lack necessary skills for proper project planning and management and large parcels are difficult to acquire. • House designs and configurations: Most Rwandans are known for large homes in comparison to other African countries. More efficient land use and housing configuration are needed to optimize floor area requirements which can significantly reduce construction costs.
issues Several problems have emerged as a result of the Nyarugenge District Plan. Firstly, a freeze on building permits issued for the renovation and expansion of existing homes promotes an inefficient outward push of residents and businesses from the city center. Consequently, many building material suppliers are going out of business. Secondly, the proposition of demolishing and rebuilding noncompliant housing places a significant burden on homeowners as well as limits the existing housing stock in the city. Lastly, strict regulations make compliance for the average household difficult, further reducing affordability. Financing
Housing Supply • High cost of construction: Traditional, local building materials and building techniques, which cost significantly less, are disallowed by the new building codes which mandate the use of steel, glass, and cement. Foreign contractors bring their own workers which are more expensive and limit the development of the local labor force. • High cost of land: Large, affordable land parcels are difficult to find within the city, as much of the land is currently occupied and subdivided.
kigal i pl anning cont ext
• High cost of construction financing: High interest rates (16-20%) and 20% upfront payment create a significant cost burden for developers. • Limited accesses to financing: High interest rates and lending policies make long-term and medium-term loans unaffordable to most individuals creating a mismatch between income levels, loan qualifications, and the price of housing. Renters have virtually no ability to borrow due to low incomes.
Recommendations In order to close to gap between affordability and supply, policy interventions in the informal sector must address housing and financing. Housing Supply • Reducing input costs to increase affordability: Exploring alternative building technologies and materials will reduce the cost of construction. Developing efficient land-use policies and smaller housing typologies can limit the amount the land consumed and lower construction costs. • High Density, low rise development to lower structural costs: Higher density, mixed-use developments that conserve land while accommodating cultural needs, can help retain existing residents and curbing sprawl, achieving cost saving benefits for all. • Incremental construction and improvements: By easing building standards to allow people to build and improve upgradeable structures incrementally, residents will be able to improve housing conditions on their own terms, increasing the viable housing stock and potential rental units in the City. Market forces and supple will begin to determine how much new construction is needed and in what time. Financing • Improving housing finance to increase effective demand for housing: This recommendation advocates for access to affordable financing at more affordable rates for developers and individuals. Promote microfinancing and home improvement loans can be a viable option as most housing in Kigali is self-built. This would coincide with easement of current building standards to accept existing housing. In addition, construction loans for new housing can incentivize new development but should be done cautiously as new construction in peri-urban and suburban areas can lead to sprawl.
Current housing conditions: formal and informal settlements
C
sustainability metrics for kigali
C1 Existing Sustainability Metrics C2 Transforming Planning Objectives into Sustainability Metrics C3 Principles, Objectives and Conceptual Metrics C4 Primary Metrics Influencing Neighborhood Form
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C Sustainability metrics for kigali C1 Existing sustainability metrics Rather than providing specific urban design recommendations for the study area, this study takes on a performance-based approach to sustainable urbanism in Kigali context. To quote Susannah Hagan; ...“‘performalism’- a direct relationship between environmental performance and urban form- can knit up culturally uninformed environmental design and environmentally uninformed urban design, particularly in cities that are growing too rapidly.” “Performalism” Environmental Metrics and Urban Design The studio’s sustainability metrics were benchmarked from various existing performance measurement guidelines such as LEED ND rating system, Center for TOD guidebook, and ASLA Sustainable Sites Initiative Guidelines & Performance Benchmarks. Due to the differences in physical context, lifestyle and level of resources for sustainable measures, many of the recommendations from these guidelines had to be tweaked to suit Kigali’s unique context.
Existing Sustainability Metrics • LEED ND • Congress for New Urbanism Sustainability Cannons • Living Cities Challenge • Model Eco Cities • Sustainability Appraisal Tools and Consulting Services -- AECOM: SSIM -- ARUP: SPeAR -- IBM: Smarter Cities Existing Urban Sustainability Metrics
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C2 Transforming Existing Planning objectives into sustainability metrics Process The existing planning work for Kigali contains robust goals for urban sustainability, which are worded n slightly different ways from one study to the next. One of the first tasks of this study was to summarize and reformulate these existing goals for urban sustainability in a manner conducive to the definition of a range actual quantitative metrics for sustainable urbanism. This exercise began with an analysis of written goals, and then moved very quickly to a range of possible strategies and means by which to measure their success. The studio’s goals for urban regulation are drawn directly from the past planning goals and themes outlined in the KCMP and the Nyarugenge District Master Plan. The two sets of goals were reorganized and synthesized into eight major categories and are meant to ensure achieving the balance of economy, ecology, and equity, the three over-arching goals of the Kigali Conceptual Master Plan.
KCMP The overarching goal of this plan is to ensure sustainable urban development in Kigali through the balancing of ecology, equity, and economy. • Protect the natural environment, exercising “best practices” to minimize environmental degradation, pollution and waste. • Promote equitable solutions that protect the interests of all people including marginal populations. • Support economic development opportunities for all with appropriate urban development and infrastructure. Ensure that urban economic growth that will also play a dynamic role in facilitating national economic growth of Rwanda.
nyarungenge district master plan The overall planning and urban design intent for Nyarugenge District are: • Revival of the Existing Central Business District and Creation of Well Distributed District Level Urban Nodes • Renewal of Existing Urban Areas • Development of Comprehensive New Townships • Creation of Alluring Recreational Features and Tourist Attractions • Transit Oriented Development supported by an Efficient and Costeffective Transportation System • Provision of Integrated, Timely, Cost Effective and Eco-friendly Infrastructure Facilities • Conservation, Revitalization and Management of the Unique and Rich Natural Features Planning Objectives from Kigali Conceptual Master Plan and Nyarungenge District Master Plan k iga li s u s ta in a b ility Me tr ic s
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C Sustainability metrics for kigali C2 Transforming Existing Planning objectives into sustainability metrics
1. Urban renewal (Economy) • “appropriate urban development and infrastructure. Ensure that urban economic growth” • “Revival of the Existing Central Business District” • “Renewal of Existing Urban Areas”
2. economic vitality (Economy, Equity) • “Promote equitable solutions” • “Support economic development opportunities for all”
5. ecological preservation and integration (Ecology) • “Protect the natural environment, minimize environmental degradation, pollution and waste” • “Conservation, Revitalization and Management of the Unique and Rich Natural Features”
6. access to Open Space (Ecology, equity)
• “facilitating national economic growth of Rwanda”
• “Protect the natural environment”
• “Development of Comprehensive New Townships”
• “equitable solutions”
3. integrated infrastructure & Energy Efficiency (Economy, ecology)
• “Creation of Alluring Recreational Features and Tourist Attractions”
7. access to local services (Economy, equity)
• “minimize environmental degradation, pollution and waste”
• “Equitable Solutions”
• “appropriate urban development and infrastructure”
• “Creation of Well Distributed Level Urban Nodes”
• “Transit Oriented Development supported by an Efficient and Costeffective Transportation System”
• “Development of Comprehensive New Townships”
8. Placemaking (Equity)
4. passive design (Ecology)
• “Equitable Solutions”
• “minimize environmental degradation, pollution and waste.”
• “appropriate urban development
• “Eco-friendly Infrastructure Facilities”
• “urban nodes” • “Renewal of Existing Urban Areas” • “Creation of Alluring Recreational Features and Tourist Attractions”
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Transforming Goals into Metrics Each of these eight goals was then broken into a series of discrete objectives with a set of corresponding design strategies. The general design strategies were then turned into sets of conceptual measures and quantitative metrics with measurable targets and thresholds specific to one of three scales: district, block and parcel/facade. A full matrix of possible metrics were explored, drawing on a variety of sources and modifying them relative the needs, goals, climate and culture of Kigali. The conceptual metrics are outlined in section C3 principles, objectives and conceptual metrics. The full working matrix is also included in appendix 1. Simultaneous with the generation of design metrics, the studio began to analyze, test and audit the existing planning and zoning implications in the chosen study area. During this phase of the work the studio began to test the impact of the various metrics as influencers or drivers of neighborhood form.
Identifying Metrics That Shape Neighborhood Form After an initial series of design scenarios, it became clear that some metrics had a much more profound influence in shaping the urban form than others, while others might exert a more profound influence at larger (city) or smaller (building) scales. This led the studio to select and focus on metrics that act as key design drivers at the urban design scale. These primary metrics influencing neighborhood form are explained in section C4 and later used as a basis for generating a range of ideal urban design scenarios in section D4, D5 & D6. Of the 8 categories of goals, all had at least one major metric which was determined to be a design driver, with the sole exception of number seven, access to local services. Both zoning and formulae for distributing public services are key to achieving this metric, but once the land use pattern is determined, as is the case in our study area, this metric has less influence over the shape of neighborhood form.
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C Sustainability metrics for kigali C3 principles, objectives and conceptual metrics The first step in developing the planning goals into measurable goals and metrics was to synthesize and reframe the two set of goals into eight categories. The eight categories are drawn directly from both the KCMP and
1. Urban renewal
the Nyarugenge District Plan, and are meant to facilitate the transition from overarching goals into comprehensive implementation strategies. For each of the eight categories, expanded objectives, strategies, and specific measures and metrics are identified.
Objective:
strategies:
• To promote revitalization of existing urban areas
• Conserve existing cultural assets • Encourage compact development
measures:
metrics:
• Conserve existing residential settlements in addition to already identified heritage buildings
• % Conserved and revitalized
• Design and build to achieve high level of density sufficient to support future public transit
• Dwelling units/Ha or FAR
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2. Economic vitality
Objective:
strategies:
• To promote socially equitable and engaging communities
• Establish mix of uses
• To promote local food production
• Encourage community based food production that will support local economic development
• To increase connectivity between key destinations to extend average stay and enhance economic performance
• Establish mixed-income diverse community
• Increase convenience and comfort of movement and reduce travel times between attractions
measures:
metrics:
• Ensure retail and neighborhood services are distributed over the residential areas
• Minimum uses per neighborhood center
• Provide a variety of housing in terms of size, type and affordability
• Simpson Diversity Index for housing
• Dedicate permanent and viable growing space and/or related facilities within project
• Growing space (sqm/DU)
• Reduce distance between destinations
• No. of destinations within 400m/800m walk
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C Sustainability metrics for kigali C3 principles, objectives and conceptual metrics strategies: • Adjust land use mix to achieve optimal balance • High levels of internal connectivity and connectivity to the community at large • Encourage multimodal travel • Minimize vehicle access requirement for single family homes
3. Integrated Infrastructure/ Energy efficiency Objective:
• To optimize land use balance in order to minimize off-site trips and reduce on-site trip length • Achieve transportation efficiency • Reduce pollution and hydrologic instability from stormwater & wastewater • Reduce energy use and adverse energyrelated environmental effects
• Design and Construct to retain stormwater on site • Encourage on-site renewable energy production to reduce the adverse environmental and economic effects associated with fossil fuel energy production and use • Encourage the development of energy-efficient neighborhoods by employing district heating/ cooling strategies
measures:
metrics:
• Encourage balanced communities with a diversity of uses and employment opportunities • Created interconnected grid of vehicular and/or pedestrian access
• % of total DU within 800m walk of full-time jobs
• Encourage use of transit/ Develop key sites to be Transit Oriented Development
• Intersection Intervals
• Provide off-site parking
• Number of bus/ train stations within 400m/800m walk
• Design and construct to retain and recycle stormwater & wastewater
• % of DU with off-site parking
• Incorporate on-site nonpolluting renewable energy generation
• Total % rainfall retained
• Incorporate a district heating and/or cooling system for new buildings
• & wastewater reused • % of on site renewable energy generation P
HOME
WORK
COMMUNITy
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80%
• & of annual heating/cooling provided by district plant
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4. PASSIve deSIgn
oBJeCTIve:
STrATegIeS:
• To reduce carbon emission impact of the project
• Optimize urban form strategies and building passive design strategies by utilizing existing urban form to reduce project overall carbon footprint
meASureS:
meTrICS:
• Maximize warming effects of the sun in winter. Maximize shade in summer.
• % Buildings be arranged to shade each other and adjacent exterior spaces
• Maximize cross-ventilation access
• % of building groups located on the middle to upper part of the slope • % of buildings rotated from cardinal axis to increase street shading • % of buildings staggered for effective ventilation Prevailing wind
• % of dwelling unit with green edges of irrigated vegetation • % of courtyards at 45o from the prevailing wind
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C Sustainability metrics for kigali C3 principles, objectives and conceptual metrics
5. Ecological Preservation and integration Objective:
strategies:
• Increase connectivity of green system by integrating ecology and urban form
• Create opportunity of interconnected ecological areas within urban area.
• Preserve existing natural features
• Minimize erosion to protect habitat and reduce stress on natural water systems by preserving steep slopes
measures:
metrics:
• Establish substantial physical green connection between open spaces • No disturbance of slopes over 20%
• Number of open spaces connected by a green corridor
• Restore the slope area with native plants or adapted plants on slopes over 20%
• % of new construction on slope over 20%
• Wetland Restoration & Preservation
• % Green restored on slope over 20%
• Water body restoration and preservation 40%
•
% Restored within 15m of wetland
• % Restored within 30m of water body
20%
20% 15m sustainabil it y m et rics f or kiga li
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6. ACCESS TO OPEN SPACE
Objective:
strategies:
• To provide open space access to all segments of resident and worker population
• Provide hierarchy and distribution of open spaces so that walking distance to population is minimized • Designate Areas for Open Space Within/Close to Homes • Facilitate Access to Open Space
measures:
metrics:
• Establish a hierarchy of park types and scales
• Types of activities: e.g. playground, bike trail, on-site program, workout stations, etc within parks
• Provide recreational facilities close to work and home to facilitate physical activity • Provide private open spaces to applicable dwelling units
• % Population within 400 m walking distance to an open space per ha
• Provide pleasant walking experience while accessing an open space
• % of parcel reserved for landscaping • % of streets that have access open space through green street connector** 15% 40% Tree canopy k iga li s u s ta in a b ility Me tr ic s
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C Sustainability metrics for kigali C3 principles, objectives and conceptual metrics
7. ACCESS TO local services
Objective:
strategies:
• To provide adequate local services to meet resident and visitor/worker needs
• Distribute neighborhood level service within walking sheds to every occupant
measures:
metrics:
• Distribute retail/food services within reasonable walking distances of residents and workers
• % population served by retail/food services within 400m distance
• Distribute public community service facilities within reasonable walking distance of residents, visitors and workers
• % population served by community service facilities within 400m distance
400m < 400m
400m < 400m Retaiil
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Community services
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8. Placemaking strategies:
Objective: • To improve physical and mental health and social capital to facilitate social networking, civic engagement, physical activity, and time spent outdoors • To activate street life
• Provide guidelines for place-making creation in the project • Establish landscape standard for public realm • Promote walking by providing safe, appealing and comfortable street environments that support public health
measures:
metrics:
• Provide hierarchy of quality civic and public space at community, district and neighborhood level
• Number of wayfinding components on site
• Create an environment that makes it easy and intuitive for users to orient themselves and navigate from place to place
• % of seating provided for total site users
• Provide outdoor seating areas
• % frontage built-to
• Increase connectivity between building façade and entries and the public realm
• Minimum distance for functional building entries
• Improve quality of walking environment
• Minimum street-facing facade setbacks
• Maximum length of blank walls • % glazing on ground level 3m
<2
60%
• Parking access from rear
40%/
15m
• % shading achieved
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C SuSTAInABIlITy meTrICS for KIgAlI C4 PrImAry meTrICS InfluenCIng neIghBorhood form ConServATIon of exISTIng BuIldIngS Conserved Building 10%
<10% slope 20%
>10% slope
PrInCIPle
1. Urban Renewal
oBJeCTIve
To promote revitalization of existing urban areas
STrATegy
ConServATIon of exISTIng BuIldIngS
level of ConTrol
District & Block Good
ConCePTuAl meTrIC
% of exisiting building stock conserved
Better
Best
Minimum 10% conservation on slope less than 10% Minimum 20% conservation on slope greater than 10%
ImPlemenTATIon guIde
Preserve habitable building stock in dense informal settlements on higher slope that may have less potential for redevelopment due to high infrastructure and constructions associated with building on steep land
SuSTAInABIlITy ImPlICATIon
Preserving existing building stock conserves resources, reduce waste, and reduce adverse environmental effects of new buildings related to materials manufacturing and transport. Preservation of the housing stock will also help to conserve the cultural landscape that represent signifi cant embodied energy and cultural value, in a manner that preserves historic materials and character-defi ning features. (Source: NYMP Table 3.3)/ GIB Credit 5/ MUD)
SuSTAInABIl IT y m eT rICS f or KIgA lI
37
Encourage compact development
PRINCIPLE
1. Urban Renewal
OBJECTIVE
To promote revitalization of existing urban areas
STRATEGY
Encourage Compact Development
Level of Control
District
CONCEPTUAL METRIC
Minimum FAR to ensure density
Implementation guide
Good
Better
Best
FAR 0.75
FAR 1.75
>FAR 3.0
Follow proposed zoning density and/or the minimum for TOD development, whichever is more stringent, to ensure sufficient density to support public transit Concentrate density along existing transportation corridor
SUSTAINABILITY IMPLICATION
Compact development promotes livability and walkability while conserving land. It also reduces public health risks by encouraging daily physical activity associated with walking and bicycling. (LEED ND NPD Credit 2, Center for TOD)
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C Sustainability metrics for kigali C4 Primary Metrics Influencing Neighborhood Form Establish Mix of Uses
Neighborhood Service
Retail
Residential
PRINCIPLE
2. Economic Vitality
OBJECTIVE
Promote socially equitable and engaging communities
STRATEGY
Establish Mix of Uses
Level of Control
Block
CONCEPTUAL METRIC
Minimum uses per neighborhood to ensure retail and neighborhood services are distributed over the residential areas
Implementation guide
Ensure retail and neighborhood services are distributed evenly so that all residential units have access to at least one in 800m (10 minute) walking distance
SUSTAINABILITY IMPLICATION
Clustering diverse land uses in accessible neighborhood and regional centers encourages daily walking, biking and transit use, reduces vehicle miles traveled and automobile dependence and supports car-free living. (Source: LEED ND NPD Credit 3)
sustainabil it y m et rics f or kiga li
Good
Better
Best
3
5
>7
39
ProvIde A vArIeTy of houSIng
Apartments with Commercial on Ground Floor
Apartment
Townhouse
PrInCIPle
2. Economic Vitality
oBJeCTIve
Promote socially equitable and engaging communities
STrATegy
ProvIde A vArIeTy of houSIng
level of ConTrol
Block
ConCePTuAl meTrIC
Minimum Simpson Diversity Index* to be 0.5 * Simpson Diversity Index Score = 1- ÎŁ (n/N)2 n = the total number of dwelling units in a single category N = the total number of dwelling units in all
ImPlemenTATIon guIde
Provide variety in terms of house size, type and affordability
SuSTAInABIlITy ImPlICATIon
Providing diverse housing types enable residents from a wide range of economic levels, household sizes and age groups to live in a community (Source: LEED NPD Credit 4).
Good
Better
Best
>05 to <0.6
>06 to <0.7
>0.7
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C Sustainability metrics for kigali C4 Primary Metrics Influencing Neighborhood Form High level of pedestrian and vehicular connectivity
<180m
<180m >10% slope
PRINCIPLE
3. Integrated Infrastructure & Energy Efficiency
OBJECTIVE
Achieve transportation efficiency
STRATEGY
High level of pedestrian and vehicular connectivity
Level of Control
District
CONCEPTUAL METRIC
Intersect interval distance
Implementation guide
Ensure maximum 180 m distance between intersections. Achieve additional pedestrian paths and intersections where construction of new vehicular road is not possible or desirable.
SUSTAINABILITY IMPLICATION
High levels of internal connectivity and connectivity to the community at large promotes multimodal transportation and reduces total vehicle miles traveled (VMT) to reach a destination, thereby reducing the negative effects of motor vehicle emissions. Encourages development within existing communities, helping to conserve land. (Source: LEED ND NPD Credit 6)
sustainabil it y m et rics f or kiga li
Good
Better
Best
180m
150m
<120m
41
mAxImIZe CroSS-venTIlATIon ACCeSS
Axis for Effective Ventilation Prevailing Wind
PrInCIPle
4. Passive Design
oBJeCTIve
Optimize urban form strategies and building passive design strategies by utilizing existing urban form to reduce project overall carbon footprint
STrATegy
mAxImIZe CroSS-venTIlATIon ACCeSS
level of ConTrol
Block
ConCePTuAl meTrIC
Percentage of courtyards over 100 sqm in size oriented 45o from the prevailing wind
ImPlemenTATIon guIde
A courtyard orientation 45o from the prevailing wind maximizes both wind in the courtyard and cross-ventilation in the buildings. Prevailing wind in Kigali in South, so orientation of South-East or South-West is recommended (See Appendix F2)
SuSTAInABIlITy ImPlICATIon
Passive design strategies buildingâ&#x20AC;&#x2122;s life-cycle cost due to innate energy effi ciency of the building form and layout. (Source: Sun, Wind and Light)
Good
Better
Best
30%
40%
>60%
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C Sustainability metrics for kigali C4 Primary Metrics Influencing Neighborhood Form Restoration of green on Slopes >40% Restored
<20% Slope
PRINCIPLE
5. Ecological Preservation and Integration
OBJECTIVE
Preserve existing natural features
STRATEGY
Restore areas of slope over 20% with native plants or adapted plants
Level of Control
District
CONCEPTUAL METRIC
% Restored on sloped area over 20%
Implementation guide
Achieve green restoration in minimum 40% of the total area over 20% slope. In addition, establish larger landscaped open space surrounding it to effectively capture stormwater runoff through the slopes and to serve as public open space for residents and workers.
SUSTAINABILITY IMPLICATION
Restoring steep slopes to a natural, vegetated state minimizes erosion to protect habitat and reduces stress on natural water systems. (Source: LEED ND SLL Credit 6)
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Good
Better
Best
40%
60%
>80%
43
create opportunity of interconnected ecological areas within urban area
15m & Max 10% Impervious
PRINCIPLE
5. Ecological Preservation and Integration
OBJECTIVE
Increase connectivity of green system by integration ecology and urban form
STRATEGY
create opportunity of interconnected ecological areas within urban area
Level of Control
District
CONCEPTUAL METRIC
Number of open spaces connected by a green corridor
Implementation guide
Good
Better
Best
2
3
>4
Minimum of 15m in width with sufficient native species or adaptive plants to support stormwater management and/ or habitat conservation in the given context Maximum 10% impervious pavements
SUSTAINABILITY IMPLICATION
With high level of interconnectivity between ecological areas, a larger ecological system is established which can support more effective stormwater management as well as habitat conservation for native animal and plant species. (Source:MUD)
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C Sustainability metrics for kigali C4 Primary Metrics Influencing Neighborhood Form provide pleasant walking experience while accessing an open space
40%
PRINCIPLE
6. Access to Open Space
OBJECTIVE
Provide open space access to all segments of resident and worker population
STRATEGY
Provide pleasant walking experience while accessing an open space
Level of Control
District
CONCEPTUAL METRIC
% green street connector over total street length
Implementation guide
Good
Better
Best
10%
15%
20%
Minimum 40% tree canopy coverage or min 20% vegetation in the right-of-way or utilizes green infrastructure such as bioswales and pervious pavement Facilitates multimodal transit (min. of 3 modes of transit)
SUSTAINABILITY IMPLICATION
Pleasant and easy access to open space encourages daily exercise and promotes more frequent access to the natural, which promotes healthier lifestyle both mentally and physically. Green streets reduce urban heat island effects, improve air quality, increase evapotranspiration, and reduce cooling loads in buildings (Source: MUD, LEED ND NPD Credit 14)
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InCreASe ConneCTIvITy BeTween BuIldIng fACAde And enTrIeS And The PuBlIC reAlm
Front Property Line
Front Property Line 0-7 m
0-7 m
PrInCIPle
8. Place Making
oBJeCTIve
Activate street life, provide safe, appealing and comfortable street environments that support public health
STrATegy level of ConTrol
InCreASe ConneCTIvITy BeTween BuIldIng fACAde And enTrIeS And The PuBlIC reAlm Block Percentage of frontage zone built-to
ConCePTuAl meTrIC Frontage Zone
Commercial/ Institutional Residential G+3 and higher
Good
Better
Best
90%
95%
100% 0-3 m
0-5 m 45o Setback from 4th level onwards
ImPlemenTATIon guIde
Frontage zone is X meters (depending on building use) from parcel edge fronting a public right of way. When two uses meet, the more stringent setback rule takes precedence.
SuSTAInABIlITy ImPlICATIon
Smaller and consistent setback creates a defi ned street edge that can help defi ne the streets as an appealing and public realm. This will in turn support public health by encouraging daily physical activity and social engagement on the streets. (Source: MUD)
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C SuSTAInABIlITy meTrICS for KIgAlI C4 PrImAry meTrICS InfluenCIng neIghBorhood form ImProve quAlITy of wAlKIng envIronmenT
Front
Parking in Rear
Front
PrInCIPle
8. Place Making
oBJeCTIve
Activate street life, provide safe, appealing and comfortable street environments that support public health
STrATegy
ImProve quAlITy of wAlKIng envIronmenT
level of ConTrol
Block
ConCePTuAl meTrIC
% Parking access from rear if applicable
ImPlemenTATIon guIde
Parking access from front is permissible if parcel sizes are too small, construction of additional service roads are not desirable, and for conserved existing buildings
SuSTAInABIlITy ImPlICATIon
By providing parking in the rear of the parking, more space of the right-of-way is given to the pedestrians, improving the safety of street environments. (Source: MUD)
SuSTAInABIl IT y m eT rICS f or KIgA lI
Good
Better
Best
80%
90%
100%
47
mInImIZe BlAnK wAllS Along SIdewAlKS
40% 15m
PrInCIPle
8. Place Making
oBJeCTIve
Activate street life, provide safe, appealing and comfortable street environments that support public health
STrATegy
mInImIZe BlAnK wAllS Along SIdewAlKS
level of ConTrol
Parcel/Street
ConCePTuAl meTrIC
Maximum length of blank walls along sidewalks (without windows or doors)
ImPlemenTATIon guIde
Target to meet “Best’ level in high density commercial zones such as C3A zone
SuSTAInABIlITy ImPlICATIon
Highly articulated building facades creates a more appealing street environment to improve pedestrian experience. Reducing the length of blank walls can also help to keep ‘eyes on the street’ to improve safety of the streets. (Source: MUD)
Good
Better
Best
40% of length or 15m
30% of length or 10m
25% of length or 8m
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C Sustainability metrics for kigali C4 Primary Metrics Influencing Neighborhood Form Increase Transparency between building and the public realm
40%
PRINCIPLE
8. Place Making
OBJECTIVE
Activate street life, provide safe, appealing and comfortable street environments that support public health
STRATEGY
Increase Transparency between building and the public realm
Level of Control
Parcel/Street
CONCEPTUAL METRIC
% of glazing on ground-level retail, services, and trade uses
Implementation guide
Windows should be designed in the style of the building and detailed to provide interest for the pedestrian. For security, open metal roller grills, providing they allow for window shopping or internal lights (offices etc.) to be seen are acceptable.
SUSTAINABILITY IMPLICATION
Shop fronts have a major impact on the quality and vitality of adjacent public footpaths and open spaces. By increasing transparency between building and the streets, visual connection is established between the two realms. (Source: MUD)
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Good
Better
Best
40%
50%
60%
49
Increase connectivity between building and the public realm
3m
<2 3m
<2
PRINCIPLE
8. Place Making
OBJECTIVE
Activate street life, provide safe, appealing and comfortable street environments that support public health
STRATEGY
Increase connectivity between building and the public realm
Level of Control
Parcel/Street
CONCEPTUAL METRIC
Functional building entries at minimum average distances along blocks
Implementation guide
entrances to a building or shop should be clearly visible and should not be obscured by columns, planting or other features. Any existing front access to floors above ground level or to basements should be retained to encourage potential residential and or mixed uses on these floors and enhance the integration of different uses by easy access.
SUSTAINABILITY IMPLICATION
Buildings with frequent and visible access from the streets add an extra dimension to the street, appearing more friendly and accessible.(Source: MUD)
Good
Better
Best
40% of length or 10m
30% of length or 10m
25% of length or 8m
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C Sustainability metrics for kigali C4 Primary Metrics Influencing Neighborhood Form Provide covered pedestrian walkways along main roads
10m 40% tree or colonnade canopy
PRINCIPLE
8. Place Making
OBJECTIVE
Activate street life, provide safe, appealing and comfortable street environments that support public health
STRATEGY
Provide covered pedestrian walkways along main roads
Level of Control
Parcel/Street
CONCEPTUAL METRIC
% shading achieved through covered walkway and/ or street trees
Implementation guide
Provide covered pedestrian walkways along shop fronts, reflecting the current building practice of Kigali.
SUSTAINABILITY IMPLICATION
Providing weather-protected walkways (especially from the sun) can improve walking experience of pedestrians. (Source: MUD)
sustainabil it y m et rics f or kiga li
Good
Better
Best
40%
60%
80%
51
k iga li s u s ta in a b ility Me tr ic s
D
testing the metrics
D1 D1.1 D1.2 D1.3
Study Area Overview Location and Existing Conditions Planning to Date Opportunities and Constraints
D2
Approach & Methodology
D3 D3.1 D3.2 D3.3 D3.4 D3.5
Testing the Existing Zoning Site Selection Zoning Massing and Implied Typology Study Zoning Evaluation Current Zoning Summary Urban Sustainability Assessment
D4 Urban Design Scenarios
D5 District Level Decision Making D5.1 Primary Metrics Influencing Neighborhood Form - District Scale D5.2 Scenario Comparison by Key Metric D5.3 Scenario Framework Comparison D6 D6.1 D6.2 D6.3
Block Level Decision Making Primary Metrics Influencing Neighborhood Form - Block Scale Block Level Massing Comparison Metric Impacts at the Block Scale
D7 D7.1 D7.2 D7.3
Street Level Decision Making Primary Metrics Influencing Neighborhood Form - Street/Parcel Scale Zoning Category Comparison by Metric Street Level Visualization Comparison
54
d TeSTIng The meTrICS meThodology And SeleCTIon In order to generate and test sustainability metrics for Kigali, a diverse study area representing a broad range of typical conditions was selected and used to explore a range of design scenarios at three distinct scales. A key study site within the Central Business District was selected to in order to test the metrics against a diverse set of urban conditions. Each scenario at the district, block, and street level was measured and tailored to meet the sustainability goals and design vision of the City of Kigali. Rather than serving as urban design plans or recommended solutions for the study area, the results of this analysis can illustrate how the city could develop under the current zoning code and subsequent how this outcome could be improved through the implementation of the recommended sustainability metrics. As a planning tool for the City of Kigali, this study is an example of how sustainability metrics can be applied to specifi c areas to meet community goals.
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55
d1 STudy AreA overvIew d1.1 loCATIon And exISTIng CondITIonS The study area borders the southern boundary of the KIST campus in the Nyarugenge District. It includes parts of the Rwezamenyo, Gitega sectors and a small section of the Nyarugenge sector. The area includes a vibrant commercial area surrounded by fi ne grain formal and informal residential settlements with relatively diverse building typologies. The study area was selected by Kigali City Planning based on the potential to study the threshold conditions between different zoning categories, as well as the siteâ&#x20AC;&#x2122;s proximity to the Central Business District and strategic location along a key transportation corridor.
Nyarugenge District Plan Land Use Plan
demoCrATIC
ugAndA
TAnZAnIA
rePuBlIC of Congo
Kigali
rwAndA
BurundI
Map of Rwanda and Neighboring Countries
Study Area Aerial View
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D Testing the Metrics D1 Study Area Overview D1.2 planning to date: Current zoning Under the current zoning code, the study area comprises three of the most common zoning categories, residential zones R2 and R3 and a mixed use zone C3A. This allows for a range of possible uses including single family houses, multifamily apartments, and mixed use development within the study area.
R2
R3
C3A
R2
Zone
FAR
Zoning Interpretation
Predominant Uses
R2
Low Rise Residential District
Low rise apartment area with a minimum plot size of 1000m2
Detached villas, semi detached and terrace houses, low rise apartments
R3
Medium Rise Residential District
Medium rise apartment district with a minimum plot size of 4000m2
Detached villas, semi detached and terrace houses, low rise apartments, medium rise apartments
C3A
City Level Commercial District
Mixed-use low rise commercial district with a minimum plot size of 250m2
Retail shops, health clinics, petrol stations, food and beverage, shopping centers/ hyper marts, boutique hotels, leisure and entertainment centres
Source: Zoning Interpretation Table 4.1 Zoning and Urban Design Guidelines Report for Nyarugenge District
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d1.2 PlAnnIng To dATe: envIronmenT PlAn (nyArugenge dISTrICT PlAn ) The study area is a highly urban area that is not directly impacted by major environmental features. The south-east corner of the study area, which is mostly zoned as R2 residential, is a relatively more sensitive area due to the proximity to the Nyamirambo Wetland Park, but little green infrastructure or recreational space exists in the main commercial area of the study area. The Environment Plan in the Nyarungenge District Plan proposes a new urban park at the south-west corner of the KIST campus. The new urban park allows for the opportunity to ecologically integrate this recreational space into the larger green network.
Source: Environment Plan, Nyarugenge District Plan
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D Testing the Metrics D1 Study Area Overview D1.2 Location and Existing Conditions topography The study area demonstrates various topographic conditions that are typical of Kigali. The most ideal site for development is the flat plateau which is currently a vibrant commercial zone bordering the KIST campus. Surrounding the flat hilltop are spots of intense slope (in red) higher than 20% on which construction is allowed only in special circumstances, as well as slope between 15-20% which are difficult to redevelop due to high infrastructure costs. Slope higher than 20%: Construction only in special circumstances
Flat plateau: Ideal for development
Slope between 15-20%: Difficult to develop, with high infrastructure costs
t est ing t he m et rics
Developable slope
59
D1.1 Location and Existing Conditions Existing buildings and zones The existing zones generally complement the proposed district zoning categories. A strong commercial district and a few civic zones are surrounding by informal single family housing zones.
Existing civic zone
Biryogo Market
Strong existing commercial district Existing civic buildings
Existing informal single family housing
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D Testing the Metrics D1 Study Area Overview D1.3 Opportunities and Constraints Views and green connections Opportunity for prime development and public use is particularly strong on the flat plateau which has unobstructed views. The unbuildable areas with slope greater than 20% can be developed into green amenities/infrastructure with potential green connections throughout.
Potential green connection
Flat plateau with unobstructed views: Ideal for prime development and public use
t est ing t he m et rics
Proposed Urban Park
Unbuildable areas can be developed into green amenities/ green infrastructure
61
D1.1 Location and Existing Conditions Transportation Corridor Due to its proximity to the central business district, the study area has a strong potential to develop the existing transportation corridor into a future bus rapid transit or other public transit corridor. Potential transit nodes, which occur at the intersection of major roads, are within a 400 m/ 8 minute walk from the majority of the study area.
Existing transportation corridor with strong potential for the development of future transit
400m or 8 minute walkingshed from future transit nodes Potential transit nodes
at the junction of major primary roads
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D Testing the Metrics D1 Study Area Overview D1.3 Opportunities and Constraints Gaps in vehicular access Despite the areaâ&#x20AC;&#x2122;s strong development potential, future development in the study area is constrained by gaps in vehicular access on parts of the hillside with no existing roads. The irregular scale and grain of the road network as well as the steep terrain can be a hindrance to immediate, cost effective development, and will prevent many parcels from reasonably complying with zoning requirements for vehicular parking provision. Areas not served by vehicular access
Irregular scale and grain of road network
t est ing t he m et rics
63
D1.1 Location and Existing Conditions inadequate water management infrastructure Inadequate water management infrastructure is another critical barrier to development. A large portion of the residential areas are currently served by untreated open, combined storm and sewer channels that pose serious health risks and pollute wetlands below.
Untreated open combined storm and sewer channels pose health risks and pollute wetlands below
Waterbody
Wetland Riparian buffer (for Nyamirambi Wetland Park) k iga li s u s ta in a b ility Me tr ic s
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D Testing the Metrics D2 Approach & Methodology Levels of Performance metrics The proposed sustainability metrics exert influence at different scales. Thus, design investigations were used to test the metrics at three distinct scales: 1. district level, 2. block level and 3. parcel/street level.
District Level
t est ing t he m et rics
Block Level
Parcel/street Level
65
levelS of PerformAnCe meTrICS The relative size and placement of the three scales are illustrated below. Nested design scenarios were generated at the district and block scales in order to test the implications of the existing planning and zoning and to offer refi ned scenarios that respond to the proposed sustainability metrics. At the parcel/ street level scale the zoning implications on typologies were tested and ultimately the infl uence of the proposed metrics were illustrated. At the block scale a sampling methodology was used to test the performance measures in a controlled and effi cient manner. Six sample study areas of 200m by 200m were selected to test and analyze how a variety of development scenarios might perform. This size was chosen because of its effectiveness for analyzing block scale massing implications. Ultimately three of these areas were used to test the existing zoning and to generate urban design scenarios.
dISTrICT
BloCK
STreeT level
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d TeSTIng The meTrICS d3 TeSTIng The exISTIng ZonIng d3.1 SITe SeleCTIon As a fi rst analytical step, development capacity under the current zoning code was analyzed. Three sites were selected and tested under the predominant zoning category of each area, illustrating implications of residential R2 and R3, and mixed-use C3A categories. Assumptions for each test include: •
Predominant zoning category considered in each sample area
•
Constant maximum FAR
•
Varying building height, lot coverage, and building setbacks
r3
C3-A
r2
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D3.2 Zoning Massing and Implied Typology Study R2 zoning massing and Implied typology study For each zoning category, various massing and parcel typologies were studied. This exercise was done to test the limits of how parcel size, setback and FAR combine to imply a particular set of building and development typologies. The goal of this exercise to is reveal the implications of the code
as written and then to explore how it might be pushed through subtle modifications. Some typologies follow the respective zoning regulation, while others test the implications of breaking certain aspects of the code such as maximum lot coverage and setback to achieve more desirable conditions.
Minimum Lot Size
FAR
Maximum Number of Floors
Maximum Building Coverage
Minimum Building Setback
1,000 m2
1.4
G+4
40%
Front 5m, Side 3m, Rear 3m
R2 Zoning Regulation for apartment
50m x 20m
33.3m x 30m 40m x 25m
Number of Floors
G+4
G+2.5
G+3
G+1.8
G+5
Building Coverage
28%
40%
35%
50%
22.30%
Building Setback
5,3,3
5,3,3
5,3,3
5,3,3
5,3,3
v R2 Zoning Massing
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D Testing the Metrics D3 Testing the Existing Zoning D3.2 Zoning Massing and Typology Study R3 zoning massing and Implied typology study
Minimum Lot Size
FAR
Maximum Number of Floors
Maximum Building Coverage
Minimum Building Setback
4,000 m2
1.6
G+7
40%
Front 7m, Side 5m, Rear 5m
R3 Zoning Regulation
80m x 50m
60m x 60.67m
40m x 100m
Number of Floors
G+7
G+3
G+4.33
G+3.2
Varies
Building Coverage
20%
40%
30%
50%
Varies
Building Setback
7,5,5
7,5,5
7,5,5
7,5,5
0,3,3
R3 Zoning Massing
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C3A zoning massing and Implied typology study
Minimum Lot Size
FAR
Maximum Number of Floors
Maximum Building Coverage
Minimum Building Setback
250 m2
2.4
G+3
80%
Front 0, Side 0, Rear 3m
C3-A Zoning Regulation
12.5m x 20m
15.5m x 16m
10m x 25m
Number of Floors
G+3
G+2.4
G+2
G+1.6
G+3.8
Building Coverage
60%
70%
80%
90%
50%
Building Setback
0,0,3
0,0,3
0,0,3
0,0,3
2,2,3
C3-A Zoning Massing
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d TeSTIng The meTrICS d3 TeSTIng The exISTIng ZonIng d3.3 ZonIng evAluATIon
ZonIng evAluATIon: r2 Zone ProS • Density supports neighborhood services and retail uses • Higher housing density increases potential proximity to transit
ConS • High costs associated with infrastructure and foundations on steep terrain • Large scale acquisition and assembly required for large minimum parcel size • Steep topography poses challenge to passive design strategies that rely on orientation • Lack of open space dedicated to individual houses • Financial and material resources require for wholesale redevelopment • Implied apartment typology not suited for steep topography
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71
ZonIng evAluATIon: r3 Zone ProS • Large minimum parcel size allows for passive orientation strategies • High housing density supports a mix of uses and public transportation
ConS • Minimum front setback discourages a continuous street frontage, walkability, and street level pedestrian activity • Low minimum lot coverage limits ability of building typologies respond to topography through terracing strategies • Allowable building height creates potential for severe scale jump • Lack of open space dedicated to individual houses • Financial and material resources require for wholesale redevelopment
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d TeSTIng The meTrICS d3 TeSTIng The exISTIng ZonIng d3.3 ZonIng evAluATIon
ZonIng evAluATIon: C3A Zone ProS • Minimum parcel size and zero front setback encourages pedestrian oriented streets with a defi ned street edge. • High density supports a mix of uses and public transportation • Small parcel sizes are conducive to incremental development
ConS • Small parcel sizes and high density can result in lack of light and ventilation to upper storeys • Allowable front loaded parking is in direct confl ict with pedestrian oriented retail • Effective parking requires coordinated efforts.
T eST Ing T he m eT rICS
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D3.4 Current Zoning Summary R2 Implied Typology P
R3 Implied Typology 7 spaces
P
c3A Implied Typology
25 spaces
P
Single Family/ Multifamily Apartments
Multifamily Apartments
4 spaces
Mixed-Use Commercial
Minimum Lot Size
150 m2 / 1,000 m2
Minimum Lot Size
4,000 m2
Minimum Lot Size
250 m2
FAR
1.4
FAR
1.6
FAR
2.4
Maximum No. of Floors
G+4
Maximum No. of Floors
G+7
Maximum No. of Floors
G+3
Maximum Building Coverage
60% / 40%
Maximum Building Coverage
40%
Maximum Building Coverage
80%
Minimum Building Setback
Front 5m / Side,Rear 3m
Minimum Building Setback
Front 7m / Side, Rear 5m
Minimum Building Setback
Front, Side 0m / Rear 3m
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d TeSTIng The meTrICS d3 TeSTIng The exISTIng ZonIng d3.5 urBAn SuSTAInABIlITy ASSeSSmenT r2 mASSIng SCenArIo
r3 mASSIng SCenArIo
C3A mASSIng SCenArIo
The R2 category, per the current zoning code, is divided into 2 types, single family dwelling units and multi-family apartments. Minimum lot sizes are 150 m2 and 1000 m2 for single family housing and multifamily apartments respectively. A range of housing typologies and maximum FAR of 1.4 helps to support economic vitality and create diverse communities. The category however is not conducive to allowing for the evolution of existing housing stock. The parking requirements also seem at odds with both the lack of existing infrastructure and larger sustainability goals.
The R3 zoning category, which consists primarily of mid-rise multi-family dwelling units, has large minimum lot sizes of 4000 m2 and a maximum FAR of 1.6. Large minimum lot sizes support high density, compact development and allow for fl exibility in passive design orientation. Downsides for this typology include increased intersection intervals and low maximum lot coverage which create a discontinuous street edge. This can result in tall buildings with large surface parking lots which may cause an unpleasant experience for pedestrians.
The C3A zoning category is perhaps one of the most conducive for achieving quality urban design solutions and incremental development. Minimum lot sizes of 250 m2 and 0 minimum setback proves advantageous as the large building coverage allows for a high percentage of frontage built to, encourages a mix of uses through high density, and provides shorter intersection intervals for an active public realm. Downsides of this category are small rear setbacks which hinder ventilation effectiveness in courtyards and allowable front loaded parking which is in direct confl ict with pedestrian oriented retail.
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R2 Implied Typology
R3 Implied Typology
+ Provision for apartments and single family houses encourages a range of housing types (Economic Vitality)
+ Large lot size gives flexibility for courtyard orientation (Passive Design) + Maximum FAR ensures
high density (Urban Renewal)
c3A Implied Typology
+ Large building coverage allows high percentage of frontage built to (Placemaking) + Small parcel size encourages short intersect interval distances (Integrated Infrastructure)
+ High density encourage mix of uses (Economic Vitality)
- Small rear setback
decreases ventilation effectiveness (Passive Making)
- Large lot size - High demand for parking places priority on vehicular travel (Transportation Efficiency) - Lack of guidelines for apartment buildingsâ&#x20AC;&#x2122; shaping of the public realm (Placemaking)
- Low lot coverage
limits percentage of frontage built-to (Placemaking)
increases intersection intervals (Integrated Infrastructure)
- Allowable front loaded parking conflicts with pedestrian oriented retail (Placemaking)
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D Testing the Metrics D4 Urban Design Scenarios Testing the Metrics at three scales As a final step the studio generated a series of urban design scenarios to test the performance of the recommended sustainability metrics. At each scale the metrics with the most profound design influence are discussed first, followed by comparison of scenarios. To begin three distinct plans were generated at the district scale using the existing zoning land-use categories and the existing basic infrastructure. While the land-use categories and mapping were maintained, other aspects of the zoning code were modified by the proposed sustainability metrics. The three scenarios balance the metrics requirements of open space, building preservation and infrastructure connectivity in different ways, but they all achieve the thresholds of the metrics. The scenarios were designed to be intentionally divergent to ensure that the metrics would allow for a diversity of possible acceptable outcomes. These are explored in section D5.
District
Next urban massing was explored at the block scale in four sample areas for each of the three district scenarios. The sample areas were selected to illustrate the issues in the different zoning categories and to explore how transitions from one zoning district to the next could be managed. For each sample area three distinct scenarios were generated and evaluated. These are illustrated in section D6. Finally the implications of the metrics for the parcel and street level scale design decisions was illustrated using a series of eye level perspectives corresponding to the four sample areas illustrating different zoning categories. These are shown in section D7.
Block
Street Level
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SCenArIoS verSuS reCommendATIonS The district and block scale examples in this study are not meant to be seen as concrete fi nalized urban design recommendations. Instead they should be understood as illustrations of diverse possible positive outcomes that the sustainability metrics could allow for. Testing several scenarios at multiple scales ensures that a variety of diverse solutions are possible, and that the proposed regulations are fl exible enough to respond to local contingencies such as market forces, neighborhood needs, ownership patterns, and development dynamics. While one scenario or another might ultimately be judged to be more successful, the primary purpose was to push and test the limits of the possible within the proposed regime of metrics. This was done in part to predict possible unintended negative implications of the regulations, thus allowing us to refi ne the rules.
SITe A SITe B SITe C
SITe d
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d TeSTIng The meTrICS d5 dISTrICT level deCISIon mAKIng d5.1 PrImAry meTrICS InfluenCIng neIghBorhood form - dISTrICT SCAle The key design drivers at district scale are preservation (conservation of existing buildings), Density (compact development to support public transit, Connectivity (vehicular and pedestrian), Open Space (restoration of green), Ecological Integration, and Access to Open Space.
STrATegy/deSIgn drIver
1.
urBAn renewAl
2.
eConomIC vITAlITy
3.
InTegrATed InfrASTruCTure
}
oBJeCTIve
}
}
goAl
To Promote Revitalization of Existing Urban Areas
Achieve Transportation Effi ciency
& energy effICIenCy
4.
PASSIve deSIgn
5.
eCologICAl PreServATIon
Preserve Existing Natural Features
And InTegrATIon
Increase Connectivity of Green System
6.
ACCeSS To oPen SPACe
7.
ACCeSS To loCAl ServICeS
8.
PlACemAKIng
T eST Ing T he m eT rICS
Provide Open Space Access to All Segments of Resident and Worker Population
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Goal
Minimum Target Levels
Conservation of Existing Buildings
Encourage Compact Development to Support Public Transit
Vehicular and Pedestrian Connectivity
Open Space Restoration
Conserve existing cultural assets
Build up residential and empoyment density along future transit corridor
Establish high level of internal connectivity and connectivity to the community at large
Preserve sensitive land and steep slopes
Minimum 10% conservation on slope under 10% Minimum 20% conservation on slope over 10%
Minimum FAR 0.75
Maximum 180 m distance between intersections
Minimum 40% restoration on slopes over 20%
Green Corridor
Green Streets
Establish open space connectivity for stormwater management, habitat restoration
Improve walking experience and facilitate peopleâ&#x20AC;&#x2122;s connectivity to nature
Green Corridor *
Green Street **
Minimum 1 landscaped Green Corridor of connecting 2 open spaces
Minimum 00% of all streets to be Green Street Connectors
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D Testing the Metrics D5 District Level Decision Making d5.2 Scenario Comparison by Key Metric
Scenario 1 Preservation: Scattered preservation by parcel conserves buildings that are of good quality, on steep slope, and/ or have historic and cultural importance. This allows for fine grain redevelopment. Connectivity: Maximum Vehicular Connections which favor vehicular travel and maximizing distances between intersections.
A B
Density: The FAR for each zoning category of R2 , R3 and C3 A are maintained at 1.4 , 1.6 and 2.4, respectively.
C D
Preserved
Green Corridor
Green Street
New Development
Open Space
Pedestrian Path Regular Road
t est ing t he m et rics
Open Space Restoration: Restoration of open space occurs on areas of steep slope with access to main roads. The open spaces run perpendicular to the slope, facilitating natural stormwater management. Green Corridor: Green corridors are located outside the urban center and act as stormwater management tools to connect open spaces to wetlands and waterbodies. Green Streets: Green streets are located on streets with the maximum vehicular traffic flow to maximize transit efficiency.
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Scenario 2 Preservation: Preservation of existing building stock occurs in clusters, conserving buildings that are of good quality, on steep slope, and/ or have historic and cultural importance. Connectivity: Balanced Vehicular & Pedestrian Connectivity is achieved through a balanced ratio between vehicular and pedestrian access.
A B
Density: The FAR for each zoning category of R2 , R3 and C3 A are maintained at 1.4 , 1.6 and 2.4, respectively.
C D
Preserved
Green Corridor
Green Street
New Development
Open Space
Pedestrian Path
Open Space Restoration: Restoration of steep slopes occurs in areas of low density and moderate vehicular access. Green Corridor: Green corridors follow natural stormwater paths and are located outside the urban center to minimize impact on existing fabric. Green Streets: Green Streets connect open spaces by the shortest distance.
Regular Road
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D Testing the Metrics D5 District Level Decision Making d5.2 Scenario Comparison by Key Metric
Scenario 3 Preservation : Preservation occurs by zones, allowing for flexible preservation and redevelopment plans. Parcels are preserved on the basis of a zone. Zones conserve buildings that are of good quality, on steep slope, and/ or have historic and cultural importance. Connectivity : Maximum pedestrian connectivity caters to pedestrian access to areas where vehicular access is not feasible.
A B
C D
Density : The FAR for each zoning category of R2 , R3 and C3 A are maintained at 1.4 , 1.6 and 2.4, respectively. Open Space Restoration : Restored open space targets areas that have limited vehicular access. Green Corridor : A more aggressive approach to green corridors brings green elements through the urban center.
Preserved
Green Corridor
Green Street
New Development
Open Space
Pedestrian Path Regular Road
t est ing t he m et rics
Green Streets : Green streets are located on streets that have the most pedestrian traffic.
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Preservation Preservation was tested by parcel, cluster and zones.
75%
75%
75% 75%
Scenario 1 % Preserved on slope <10% % Preserved on slope >10%
Preserved on <10% Slope
Scenario 2
13 %
% Preserved on slope <10%
25 %
% Preserved on slope >10%
Scenario 3
10 %
% Preserved on slope <10%
10 %
30 %
% Preserved on slope >10%
20 %
<10% Slope
Preserved on >10% Slope
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D Testing the Metrics D5 District Level Decision Making d5.2 Scenario Comparison by Key Metric Connectivity Scenarios vary in number of new pedestrian and vehicular connections.
Scenario 1 Average Vehicular Intersection Interval New Vehicular Intersections Average Pedestrian Intersection Interval New Pedestrian Intersections Vehicular Intersection Interval Existing New <120m
Scenario 2
93 m
+ 20 59 m
+18
Average Vehicular Intersection Interval New Vehicular Intersections Average Pedestrian Intersection Interval New Pedestrian Intersections
Pedestrian Intersection Interval Existing New <120m
120-140m
120-140m
140-180m
140-180m
t est ing t he m et rics
Scenario 3
89 m
Average Vehicular Intersection Interval
+34
New Vehicular Intersections
+10
New Pedestrian Intersections
41 m
Average Pedestrian Intersection Interval
94 m
+40
84 m
+60
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Open Space Restoration Preservation was tested by parcel, cluster and zones.
Scenario 1 % of >20%Slope Restored as Open Space Total Open Space Area
Scenario 2
44 %
% of >20%Slope Restored as Open Space
94,236 sqm
Total Open Space Area
Green Corridor
>20% Slope
Open Space
Restored Green
Scenario 3
59 %
% of >20%Slope Restored as Open Space
44 %
66,857 sqm
Total Open Space Area
79,204 sqm
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D Testing the Metrics D5 District Level Decision Making d5.2 Scenario Comparison by Key Metric Green Corridor Scenarios vary in number of new pedestrian and vehicular connections.
Scenario 1 No. of Open Spaces Connected by Green Corridor Total Green Corridor Area
Scenario 2
2
No. of Open Spaces Connected by Green Corridor
25,377 sqm
Total Green Corridor Area
Green Corridor Open Space
t est ing t he m et rics
Scenario 3
4
No. of Open Spaces Connected by Green Corridor
7
12,337 sqm
Total Green Corridor Area
22,975 sqm
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Green streets Preservation was tested by parcel, cluster and zones.
Scenario 1 Total Green Street Length % of Green Streets over Total Street Length
Scenario 2
4,047m
Total Green Street Length
19.0 %
% of Green Streets over Total Street Length
Scenario 3
2,583m
Total Green Street Length
3,004m
14.1%
% of Green Streets over Total Street Length
13.8 %
Green Corridor Open Space
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D Testing the Metrics D5 District Level Decision Making d5.3 Scenario Framework Comparison
Scenario 1
Scenario 2
Scenario 3
Preservation By Parcel
By Cluster
By Zone
Connectivity Maximum Vehicular Connectivity
Balanced Vehicular & Pedestrian Connectivity
Maximum Pedestrian Connectivity
Density Meet Zoning Requirement
Meet Zoning Requirement
Meet Zoning Requirement
Open Space Restoration Maximize Open Space Access to Roads
Restore Areas with Lower Density & Moderate Vehicular Access
Restore Areas Less Accessible by Vehicles and More Accessible by Pedestrians
Green Corridor Locate Green Corridors Outside the Urban Center, Connect Restored Open Space to the Wetland System
Locate Path that Least Disturbs the Existing Fabric, Build On Top of Natural Stormwater Path to Connect Restored Open Space to Each Other
Establish More Aggressive Green Corridor throughout the Urban Center
Green Street Green Streets with the Most Vehicular Flow
t est ing t he m et rics
Green Streets that Provide Shortest Distance to Parks
Green Streets with the Most Pedestrian Flow
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Scenario 1: Overall Framework
Pros • Improves Efficiency of Vehicle Travel • Allows for Finer Grain Redevelopment
Cons • Potential Difficulty in Assembling Larger Parcels Due to Conserved Buildings
Preserved
Green Corridor
Green Street
New Development
Open Space
Pedestrian Path Regular Road
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D Testing the Metrics D5 District Level Decision Making d5.3 Scenario Framework Comparison Scenario 2: Overall Framework
Pros • Preserves Existing Urban Fabric • Minimizes Impact of New Green Systems on the Existing Urban Fabric
Cons • Large Clusters of Preserved Areas May Not Integrate Well With Future Developments
Preserved
Green Corridor
Green Street
New Development
Open Space
Pedestrian Path Regular Road
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Scenario 3: Overall Framework
Pros • Establishes Pedestrian Friendly Development • Maximizes Pedestrian Access to Green
Cons • Limited Road Access to Open Space • Green Corridor through Urban Center May Not be Ecologically Effective and Interrupt Traffic Flow
Preserved
Green Corridor
Green Street
New Development
Open Space
Pedestrian Path Regular Road
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d TeSTIng The meTrICS d6 BloCK level deCISIon mAKIng d6.1 PrImAry meTrICS InfluenCIng neIghBorhood form - BloCK SCAle The key design drivers at block scale are Preservation (conservation of existing buildings), Mixed Uses, Mixed Housing Types, Courtyard Orientation, Building Setbacks and Frontage Built-To, and Parking Access
STrATegy/deSIgn drIver
1.
urBAn renewAl
2.
eConomIC vITAlITy
3.
InTegrATed InfrASTruCTure & energy effICIenCy
4.
PASSIve deSIgn
5.
eCologICAl PreServATIon
}
oBJeCTIve
}
}
goAl
To Promote Revitalization of Existing Urban Areas
Promote Socially Equitable and Engaging Communities
To Reduce Carbon Emission Impact of the Project
ACCeSS To oPen SPACe
7.
ACCeSS To loCAl ServICeS
8.
PlACemAKIng
Promote Walking by Providing Appealing and Comfortable Street Environment that Support Public Health
Front Property Line
6.
0-3 M
T eST Ing T he m eT rICS
Front Property Line
And InTegrATIon
0-3 M
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Conserved Building
Retail
Apartments with Neighborhood Commercial at Service Apartment Ground Floor
Goal
Minimum Target Levels
Conserve existing cultural assets
Minimum 10% conservation on slope under 10% Minimum 20% conservation on slope over 10%
mixed uses
mixed housing Types
Prevailing Wind
Courtyard orientation
Distribute Retail and neighborhood services over the residential areas
Provide a suffi cient variety of housing sizes and types
Orient courtyards 45o from the prevailing wind
Minimum 3 kinds of uses per neighborhood center
Minimum Simpson Diversity Index* to be 0.5
40% of courtyards of over 100sqm oriented at the specifi ed angle
Front Property Line
Conservation of existing Buildings
Townhouse
Front Property Line
Residential
0-7 m
0-7 m
Building Setback and frontage Built-to Minimum streetfacing building faรงade setbacks Maximum building frontage built-to Maximum 7m setback Minimum 60% of parcel frontage built-to
Parking in Rear
Parking Access
Provide parking access from rear if possible
Minimum 80% parking accessed from rear
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d TeSTIng The meTrICS d6 BloCK level deCISIon mAKIng d6.2 BloCK level mASSIng ComPArISon
Preserved
Green Corridor
The following comparisons illustrate development potential for each of the four study areas in conjunction with the three district level framework plans.
New Development
Green Street Open Space
SITe A: r3 & C3A
Scenario 1
Scenario 2
Scenario 3
Pros High portion of frontage built-to. Existing and new buildings are well integrated.
Strong, well defi ned pedestrian scale network by limiting street-facing building facade setback.
Clusters of preserved buildings allow for a mix of scales and incomes.
Cons R3 blocks are very large and interrupt the existing grid.
T eST Ing T he m eT rICS
Parking access from front in residential area. Conserved buildings are less integrated.
R3 blocks are very large and interrupt the existing grid.
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Preserved
Green Corridor
New Development
Green Street Open Space
SITe B: C3A
Scenario 1
Scenario 2
Scenario 3
Pros Scattered preserved buildings allow for a mix of scales and incomes.
Clusters of preserved buildings allow for a mix of scales and incomes.
Green network has a strong presence in the mixed-use area.
Cons Presence of green network is limited.
Presence of green network is limited.
Lack of preservation.
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d TeSTIng The meTrICS d6 BloCK level deCISIon mAKIng d6.2 BloCK level mASSIng ComPArISon
Preserved
Green Corridor
New Development
Green Street Open Space
SITe C: C3A & r2
Scenario 1
Scenario 2
Scenario 3
Pros Scattered preserved buildings allow for a mix of scales and incomes. Multiple green corridors.
Possible to preserve existing successful commercial block that already has good relationship to the streets and they can be integrated with the new development.
Green network connects mixed-use and housing areas.
Cons Vehicular access challenging on steep slopes. T eST Ing T he m eT rICS
Low level of vehicular access in the preserved R2 zones.
Low level of vehicular access in preserved R2 zones.
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Preserved
Green Corridor
New Development
Green Street Open Space
SITe d: r2
Scenario 1
Scenario 2
Scenario 3
Pros Scattered preservation facilitates mixed housing types in neighborhood.
Large parcel size meets courtyard orientation requirement.
Strong relationship between housing and open space network.
Cons Large building setback on major street due to single family parking requirements.
Poor frontage built-to creates discontinuous street edge along green street.
Lack of preservation.
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D Testing the Metrics D6 Block level Decision Making d6.3 metric Impacts at the block scale Conservation OF eXISTING hOUSING In addition to the conservation of buildings with cultural significance, preservation of existing building stock is based on quantitative and sustainability measures in order to meet housing demand and development capacity as the City of Kigali urbanizes. Criteria for preservation includes: •
Conservation of of urban fabric and buildings of historic significance helps in retaining the existing cultural context.
•
Conserve minimum 10% of land with slope < 10%
•
Conserve minimum 20% of land with slope > 10%
•
Preserve buildings with durable construction and the potential for expansion
•
Preserve buildings with uses that are significant economic drivers or social service providers
•
Conserve areas with limited vehicular access.
Slope < 10%
Slope > 10%
Conserved on Slope Less than 10% Conserved on Slope Greater than 10%
t est ing t he m et rics
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mixED uSES A variety of uses including commercial, retail, residential, and neighborhood services within proximity to one another creates a diverse, mixed-income community. Uses can be mixed through floor plates, such as offices or residential uses above ground floor retail. Institutional buildings in close proximity to the residential uses such as schools, hospitals, and religious institutions support economic vitality and social equity.
Neighborhood Services
Office
Residential
Retail
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D Testing the Metrics D6 Block level Decision Making d6.3 metric Impacts at the block scale mIXED hOUSING tYPES A variety of housing creates a diverse community through economic stability and bridges the gap between supply, demand, and affordability. By providing a range of options, housing supply can meet market demands and cater to a variety of people at various income levels. Housing typologies include single family residential, mixed single family housing, attached and detached houses, town houses and apartments.
Residential with Commercial Below Apartment
Preserved Single Family Housing
t est ing t he m et rics
Townhouse
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CourTyArd orIenTATIon Due to the moderate climate of Kigali, passive design strategies on capitalize on environmental conditions to maximize cross ventilation and natural daylighting. 40% of courtyards greater than 100 m2 should be oriented 45o from the prevailing wind (South) to maximize both wind in the courtyard and cross ventilation in the buildings around it.
n
Prevailing wind
Prevailing wind
Source: http://mesonet.agron.iastate.edu
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D Testing the Metrics D6 Block level Decision Making d6.3 metric Impacts at the block scale setback and frontage built to By achieving a minimum of 80% build to for parcel frontage and siting buildings within setback zones, the connectivity between building faรงades, entries and the public realm increases to activate street life. Modifications to plot coverage rules in the R3 zoning category as well as the establishment of minimum and maximum setback zones are required to achieve suggested minimum frontage build to.
Small Street-facing Facade Setback
Large Portion of Parcel Frontage Built-to
t est ing t he m et rics
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parking access Shared parking access from the rear maximizes the building frontage creating a strong urban edge for the commercial district, This can be achieved by requiring a minimum of 80% parking access in the rear and coordinated efforts to provide shared parking and service alleys at the block level. Parking access from the front is permissible if parcel sizes are too small, construction of additional service roads are not desirable, and for conserved existing buildings.
Parking Access from Front
Parking Access from Rear
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d TeSTIng The meTrICS d7 STreeT level deCISIon mAKIng
JunCTIon of r3 And C3A
C3A TyPICAl
SITe A SITe B r2 TyPICAl
SITe C
SITe d
TeSTIng PerformAnCe AT STreeT level
green CorrIdor Through C3A
T eST Ing T he m eT rICS
Four sample sites were designed to illustrate key design drivers at the parcel/ street level. In addition to the larger block and district scale measures that shaped overall framework and massing, levels of performance for each of the parcel/ street level metrics will provide sitespecifi c solutions.
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STreeT level meThodology Each of the four street level locations were selected from the twelve framework scenarios developed for block level design drivers. These images illustrate elements of the existing building codes as well as design drivers developed from the sustainability metrics
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d TeSTIng The meTrICS d7 STreeT level deCISIon mAKIng d7.1 PrImAry meTrICS InfluenCIng neIghBorhood form - STreeT/PArCel SCAle The key design drivers at street scale are facade articulation (blank walls, glazing), connectivity between building and streets (building entries interval), and percentage shading.
STrATegy/deSIgn drIver
1.
urBAn renewAl
2.
eConomIC vITAlITy
3.
InTegrATed InfrASTruCTure
}
oBJeCTIve
}
}
goAl
& energy effICIenCy
4.
PASSIve deSIgn
5.
eCologICAl PreServATIon And InTegrATIon
6.
ACCeSS To oPen SPACe
7.
ACCeSS To loCAl ServICeS
8.
PlACemAKIng
T eST Ing T he m eT rICS
Promote Walking by Providing Appealing and Comfortable Street Environment that Support Public Health
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3m
40%
3m
60%
<2
15m
Blank walls along Side walks
ground level retail, Services, and Trade uses glazing
<2
functional Building entries
10m 40% Shading
Street Shading
Goal
Maximum length of blank walls along sidewalks (without windows or doors)
Maximum glazing on ground-level retail, services, and trade uses
Functional building entries at minimum average distances along blocks
Maximum shading achieved through covered walkway and/ or street trees
Minimum Target Levels
Minimum 40% of length or 15m
Minimum 60% glazing
23m or less
Minimum 40%
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D Testing the Metrics D7 street level Decision Making d7.2 Zoning Category Comparison by metric Blank walls comparison
C3A Typical % Blank wall length along sidewalks
% Blank wall length along sidewalks
25%
30%
R2
Green Corridor
% Blank wall length along sidewalks
35% t est ing t he m et rics
R2 & C3A
% Blank wall length along sidewalks
27%
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glazing comparison
C3A Typical
R2 & C3A
% Glazing on ground level retail, services and trade uses
% Glazing on ground level retail, services and trade uses
68%
66%
R2
Green Corridor
% Glazing on ground level retail, services and trade uses
N/A
% Glazing on ground level retail, services and trade uses
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D Testing the Metrics D7 street level Decision Making d7.2 Zoning Category Comparison by metric functional building entrance comparison
t est ing t he m et rics
C3A Typical
R2 & C3A
Average distance of functional building entries along blocks
Average distance of functional building entries along blocks
6.5m
5.1m
R2
Green Corridor
Average distance of functional building entries along blocks
Average distance of functional building entries along blocks
20.6m
6.6m
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shading comparison
C3A Typical % Shading over streets
R2 & C3A % Shading over streets
66%
60%
R2
Green Corridor
% Shading over streets
58%
% Shading over streets
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D Testing the Metrics D7 street level Decision Making d7.3 street level visualization typical R2
Low rise apartment
Slope over 20%
BEFORE
New single family house
Low rise apartment
AFTER 5m front setback
Discontinuous street edge
t est ing t he m et rics
Preserved single family house
Open space on restored slope
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typical r2
Blank Walls Higher % of blank walls along sidewalks for residential privacy, especially in preserved houses Glazing Glazing on street level is not required for residential buildings Functional Building Entrances Less frequent building entrances for apartment buildings and more frequent in townhouse and single family house areas Shading Provided by indigenous trees Pros Lower transparency along sidewalks protect residentsâ&#x20AC;&#x2122; privacy Cons Limited connection between buildings and the public realm and lack of ground level services reduce street activities
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D Testing the Metrics D7 street level Decision Making d7.3 street level visualization Comparison typical C3A
Residential/ office over ground floor commercial
BEFORE
AFTER Zero front setback
Covered pedestrian walkway required in the zoning code
t est ing t he m et rics
Covered pedestrian walkway required in the zoning code
Street trees provide shading along the street and sidewalk
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typical c3a
Blank Walls Lowest % of blank walls along the shop fronts Glazing Highest % of glazing for commercial street frontage Functional Building Entrances Frequent retail store doors and doors for apartments above commercial use Shading Covered pedestrian walkways are provided when the sidewalks are not wide enough for large canopy tress for shading Pros Highly articulated and sidewalk-facing facade provides visual interest for users of the commercial street. Frequent entries to shops from the streets facilitate customer access Cons High percentage of glazing may cause issues with maintenance and safety
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D Testing the Metrics D7 street level Decision Making d7.3 street level visualization Comparison junction of r3 an c3a
Medium rise apartment
Parking lot along street edge for residential apartments
BEFORE
Single family Townhouse
Medium rise apartment
Preserved commercial buildings
AFTER 7m front minimum setback
Existing commercial buildings
t est ing t he m et rics
Raised front porch in build to zone creates privacy for residents
Street trees provide shading along the street and sidewalk
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junction of r3 an c3a
Blank Walls Moderate % of total blank walls due to mix of residential and commercial uses Glazing Relatively lower total % glazing due to mix of residential and commercial buildings Functional Building Entrances Entries into townhouses are not as frequent as those for shops on the other side of the street Shading Shading is provided more aggressively on the commercial side with covered pedestrian walkways and continuous street trees, to direct people more to the retail side while keeping the residential side less crowded Pros Mix of commercial and residential buildings and high visual connectivity between the two can increase safety, with eyes on the street from dwelling units throughout the day Cons Residential privacy may be compromised due to continuous activity of people on commercial streets
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D Testing the Metrics D7 street level Decision Making d7.3 street level visualization Comparison green corridor through c3a
Residential/ office over ground floor commercial
BEFORE
Green corridor
Green roof
AFTER Zero setback
Covered pedestrian walkway required in the zoning code
t est ing t he m et rics
Street trees provide shading along the street and sidewalk
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green corridor through c3a
Blank Walls Lowest % of blank walls along the shop fronts due to high level of glazing and frequent entries Glazing Big windows at street level for retail stores Functional Building Entrances Frequent entrances into the retail stores and for apartments on upper stories Shading Deep covered pedestrian walkways for weather protection and shade from densely planted trees in the green corridor Pros Green corridor and highly articulated building facades provide pleasant and interesting walking experience for pedestrians Cons Wide green corridor in the middle of the retail street may weaken commercial vibrancy, as opposed to having stores on both side of the street
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Conclusions and Next steps
E1 Conclusions E1.1 Major Sustainable Urbanism Metric Topics E1.2 Analysis and Recommendations
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E Conclusions and next Steps E 1 Conclusions It is important to reiterate that the metrics proposed in this document are an interpretation of the sustainability goals proposed in the official planning documents for Kigali. This document translates the stated goals into quantitative metrics for urban sustainability. These metrics are drawn from a variety of sources including LEED ND, Living Cites, and other best-practices sources for urban sustainability and urban design. In a few cases they have been devised specifically for the Kigali context. To be considered final, the metrics will require further study to test their appropriateness for Kigaliâ&#x20AC;&#x2122;s culture, climate and development dynamics. Also important to note is the fact that our conclusions about the existing planning mechanisms are limited to three common zoning categories and are based on an analysis of the typologies implied by the current zoning code and an analysis of scenarios developed at the district, block, and parcel/ street levels. These are starting points for judging the effectiveness of the developed metrics as well as providing recommendations for improving the current building standards. Our analysis suggests that some of Kigaliâ&#x20AC;&#x2122;s goals for urban sustainability are well supported by the planning tools in place, while some goals would benefit from stronger regulatory tools. In a few cases it appears that none of the planning mechanisms in place will ensure that the proposed sustainability goal will be met. Aspirations of achieving high density and a mix of uses through new development and the provision of open space are strong aspects of the current planning regime and are highly successful at the district and block scales. Tools that support the preservation of building stock and heritage, and by extension resource and material conservation, are less robust. While the preservation and restoration of existing buildings is detailed in the Conservation and Heritage Control Plan of the Nyarugenge District Plan, stronger tools are needed for preservation of existing building stock in the larger context. Methodologies for preservation decision making also appear to be lacking beyond buildings of high cultural significance. In addition, guidelines for ecological integration and connectivity of open space are limited, although planning articulates these as goals. The largest gaps in the existing planing tools are centered around placemaking where design
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standards that improve the public realm, promote a pedestrian oriented environment and activate street life are significantly lacking in the existing code. Of particular concern in this area are the standards for provision and integration of automobile parking as it relates to the existing urban fabric and its impact on new development. Another area of concern is limited set of tools for ensuring that buildings support and active and pedestrian oriented public realm by defining and actively relating to the street. As next step, our recommendation is that the proposed sustainability metrics be examined more carefully and that some of the tools that are lacking or missing form the regulatory structure be explored. We would also recommend testing the other zoning categories in a similar fashion to the method used in this study. Many of the metrics generated for Kigali merit more careful study and refinement. More in depth analysis of how the types of controls recommended here could be implemented in practice is also needed to move any of these recommendations forward. The following pages highlight key recommendations organized around the eight categories of sustainability metrics: 1.
Urban Renewal
2.
Economic vitality
3.
Integrated infrastructure & Energy Efficiency
4.
Passive Design
5.
Ecological preservation & Integration
6.
Access to Open Space
7.
Access to Local Services
8.
Placemaking
1. urBAn renewAl 2. eConomIC vITAlITy 3. InTegrATed InfrASTruCTure & energy effICIenCy 4. PASSIve deSIgn 5. eCologICAl PreServATIon And InTegrATIon 6. ACCeSS To oPen SPACe 7. ACCeSS To loCAl ServICeS 8. PlACemAKIng
}
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economy ecology equity
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E Conclusions and next Steps E 2 Analysis and recommendations Existing planning Tools Meeting Sustainability Metrics
Urban renewal â&#x20AC;˘
HIgh Density COmpact Development
Economic Vitality â&#x20AC;˘
Mix of uses
Ecological preservation & integration â&#x20AC;˘
Maximum FAR under existing zoning code ensures high levels of density.
High housing density in residential and mixed use zones is achieved under current zoning code through maximum FAR. In order to meet the recommended baseline measures, new development should aim at achieving a minimum FAR of .75.
Permitted and conditional uses under current zoning categories range from 2-4 uses per zone.
Target minimum uses per neighborhood as recommended in the sustainability metrics are achieved under current zoning code. In areas of low density residential development, conditional uses provide neighborhood scale services.
Preservation and restoration of ecologically sensitive lands restores natural ecosystem.
Preservation of wetlands and slopes greater than 20% is achieved under current zoning code and Nyarungenge District Plan. This also includes establishment of a 20 m riparian buffer for wetland protection.
Provision of open space at district level
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Existing planning Tools Requiring Stronger Measures
Urban renewal â&#x20AC;˘
Preservation & Conservation
Passive Design â&#x20AC;˘
Energy Efficiency and Green building technologies
Conservation and Heritage Control Plan identifies key structures to be preserved but larger tools needed for conservation of existing housing stock beyond cultural and heritage measures
In order to meet housing demand and development capacity as the City of Kigali urbanizes, stronger tools are needed to rationalize preservation of some of the existing building stock. This new criteria should compliment culturally based preservation methods as well as include quantitative and sustainability based measures. Our recommendation is that a minimum of 10% of building stock on land with slope less than 10% and 20% of building stock on land with slope greater in 10% be preserved to protect the cultural and social characteristics of Rwandan housing. This practice would also have an effect of preserving a mix of income levels within existing districts.
Coverage bonuses awarded for use of sustainable building design technologies under existing building code, however, green design for new construction is not a mandate
In addition to sustainability best practices and exploration of green building practices in the context of Kigali, it is important to capitalize on passive design strategies that reduce energy demands. Our recommendation is that: 1. Buildings be staggered for effective ventilation. 2. 40% of courtyards greater than 100 m2 should be oriented 45° from prevailing wind to maximize effective ventilation. k iga li s u s ta in a b ility Me tr ic s
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E Conclusions and next Steps E 2 Analysis and recommendations Existing Planning tools Requiring Stronger Measures
Ecological preservation & integration â&#x20AC;˘
Neighborhood scale urban park identified in Nyarungenge District Plan but integration of ecology into urban fabric missing.
Neighborhood Scale urban Park
Ecological preservation, restoration, and integration at the neighborhood and district scales are important for creating healthy, sustainable communities. In order to ensure integration of stormwater management techniques and protection of environmentally sensitive slopes, it is recommended that: 1. One green corridor, as defined in the metrics, connect a minimum of two open spaces. 2. New construction on slopes greater than 20% be limited to 10% in order to minimize environmental impact and high infrastructure costs. 3. A minimum of 40% of land on slopes over 20% be restored
Access to OPen Space â&#x20AC;˘
Facilitate Access to Open SPace
The provision of a continuous green network accessible to all residents is outlined in the Nyarungenge District Plan, but connectivity means not identified.
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Stronger tools are needed to provide continuous connections between green spaces in order to manage storm water as well as provide easy access to passive and recreational open spaces. It is recommended that: Streets that provides access to open spaces should be designated as green street connectors, as defined in the metrics. The location and extent of green street connectors should be established during the mater planning phase in order to align with framework plans and minimize construction costs.
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criteria missing from existing pLanning Tools
Integrated Infrastructure/ Energy Efficiency â&#x20AC;˘
multimodal transit
High demand for single family parking favors vehicular travel over other modes of transit.
A major component of the sustainability plan is the reduce the number of vehicle miles traveled and dependency on personal automobiles through compact development and improvements in public transportation options. The biggest hindrances to achieving transportation efficiency are parking requirements for single family dwelling units, requiring 2 spaces for each home. In order to cut down on high costs associated with construction of new infrastructure that would serve each home, and align with current transit preferences of Kigali residents, it is recommended that: 1. On-site parking be limited for single family homes by providing shared parking facilities and less required parking spaces for 50% of homes. Implementation requires a change in the building code to streamline and tailor parking requirements to the context of Kigali and current transit needs. 2. Provide access to transit through interconnected public transportation system through reliable public transit and convenient stops/ stations.
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E Conclusions and next Steps E 2 Analysis and recommendations criteria missing from existing planning Tools
Placemaking â&#x20AC;˘
Promote walking through safe pedestrian environment
Minimum front setbacks in residential zoning categories discourages a continuous street frontage, walkability, and street level pedestrian activity.
A continuous street edge is important for defining the public realm. In addition to appropriate massing and location of buildings along the street edge, building features can help create a safe and vibrant walking environment. After extensive analysis of the current building code, it is recommended that: 1. Maximum setbacks be established in addition to the revision of minimum setbacks. Buildings should build to a minimum of 80% of the front lot line and fall within the maximum setback zone*. 2. Blank walls at ground level not to exceed 40% of the total building frontage. 3. 60% minimum glazing at ground level to create transparent pedestrian atmosphere.
Establish landscape standards for the public realm to activate street life and regulate parking along building frontages â&#x20AC;˘
Improve quality of walking environment
4. 23m maximum average between functional building entries in residential zones, 5. Provide parking access from rear when applicable through coordinated efforts and service alleys at the block level. 6. Achieve 40% shading along the street through street trees and other shading devices to maximize comfort and protection from weather.
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F
F1 F2
Appendix Sustainability Metric Matrix for Kigali Kigali Climate Analysis
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F appendix F1 Sustainability Metrics for Kigali
1
Urban Renewal
Objectives
To promote revitalization of existing urban areas
Strategies
Promote socially Mix of Uses equitable and engaging communities Mixed-income diverse community
Economic Vitality
Design and build to achieve high level of density sufficient to support future public transit
Metrics
DU/ha or FAR District
Max FAR ensures high levels of density
Permitted uses in each zonEnsure retail and ing category ranges from 2-4 neighborhood services uses/ Conditional uses in Block are distributed over R2-R4 zoning and Permitted the residential areas uses in Commercial zoning districts Provide a Variety of N/A Should include a range of Block Housing housing options
Design Driver Residential Density (Units/ HA) Balanced (Units/HA) Employment (Units/HA)
Community-based food production to support local economic development
To increase connectivity and access between key destinations to extend average stay and enhance economic performance
Increase convenience and comfort of moveReduce distance bement and reduce travel tween destinations times between attractions
* Simpson Diversity Index Diversity of housing includes diversity of housing type (single family, townhouse, apartment, etc), housing size and level of affordability
District N/A
Good
Target Better
Best
10% of land with slope < 10% 20% of land with slope >10%
>25 >62.5 >157.5 DU/Ha DU/Ha DU/Ha or 0.75 or 1.75 or 3.0 FAR FAR FAR 29-57 58-120
>121
17-34 35-114 23-51 52-120
>115 >121
Design Min uses per neighborhood Driver center
3 Uses 5 Uses 7 Uses
Design Simpson Diversity Index* Driver
>05 to >06 to <0.6 <0.7
Dedicate permanent N/A in all zoning categories and viable growing Parcel/ except for P3 Agricultural space and/or related District Areas facilities within project
Local Food Production
appendix
Level of Control in Current Zoning Code Control
Conservation and heritage control plan (6.4) identifies Conserve existing structures and provides remits residential settlements for preservation, C3A protects Conserve existing culParcel/ Design in addition to already cultural and historical charac% Conserved and Revitalized tural assets District Driver identified heritage ter through small parcels and buildings low maximum building height, but specific percentages for preservation are not listed.
Encourage Compact Development
2
Measures
Priority Level
Topic
Growing space (sqm/DU)
5.6 sqm/ DU
10 sqm/ DU
Data Source / Assumptions
(NYMP Table 3.3)/ GIB Credit 5/ MUD
LEED ND NPD Credit 2 Center for TOD Development LEED ND NPD Credit 3
>0.7
LEED NPD Credit 4
18.5 sqm/ DU
LEED NPD Credit 13
NEIGHBORHOOD scale: No. of destinations within 400 2 uses/ 3 uses/ 4 uses/ m DISTRICT scale: No. of 1 use 2 uses 3 uses destinations within 800 m
MUD
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Objectives
Strategies
3
Integrated Infrastructure / Energy Efficiency Reduce pollution and hydrologic instability from stormwater
Reduce pollution from wastewater and encourage water reuse
Reduce energy use and adverse energy-related environmental effects
Level of Control in Current Zoning Code Control
Target
Metrics
Encourage balanced RESIDENTIAL: % of the communities with a dwelling units within 800m diversity of uses and District N/A walk distance of existing fullemployment opportime jobs tunities Created interconPedestrian access through nected grid of vehicuparcels should be continuous High levels of internal lar and/or pedestrian and provide access to local connectivity and con- access (Require at Parcel/ Design transit stops, continuous Intersection interval distance nectivity to the commu- least one throughDistrict Driver covered walkway along street nity at large passageway for paredge in commercial zoning cels exceeding 180m districts in length) Transit N/A in residential zoning, Public bus transit Residential Transit Acintegration into C2 districts, cess: The integration of transit stops into number of bus Balanced commercial development lots, routes and minimum of one taxi stand train stations Encourage use of tranwithin lot boundary, and pewithin 400m Encourage multi-modal sit/ Develop key sites Parcel/ destrian linkage to bus stops and 800m travel to be Transit Oriented District in C3 (where applicable), Development walk Integration of bus stop and/or Employrespectively light rail into commercial lot, ment (from any provision of at least one taxi location within stand, and pedestrian linkage TOD) to transit stop in C4, C4A, C5 (where applicable) Minimize vehicle acN/A, parking requirements per Provide off-site cess requirement for Parcel % DU with off-site parking parking parcel basis single family homes Design and construct to retain at least 80% Total percentile rainfall volParcel N/A Design and Construct of the average annual ume to be retained to retain stormwater stormwater Design and construct on site Total percentile rainfall volto manage stormwater District N/A ume to be retained runoff at district level Design and construct to retain at least 25% Design and Construct of the average anPercentage of wastewater to recycle wastewater Parcel N/A nual waster water, and reused on site reuse that waster to replace potable water. Encourage on-site Incorporate on-site renewable energy prononpolluting renewduction to reduce the able energy genadverse environmental Percentage of on-site reneweration, such as solar, Parcel N/A and economic effects able energy generation wind, geothermal, associated with fossil small-scale or micro fuel energy production hydroelectric and use Encourage the deIncorporate a district velopment of energyheating and/or coolPercentage of annual heatefficient neighborhoods ing system for new District N/A ing/cooling consumption proby employing district buildings (at least two vided by the district plant heating/cooling stratebuildings total) gies
Adjust land use mix to achieve optimal balance
To optimize Land Use Balance in order to minimize off-site trips and reduce on-site trip length
Measures
Priority Level
Topic
Data Source / Assumptions
Good
Better
Best
30%
50%
>70%
150m
“Good” from LEED ND <120m NPD Credit 6/ SLL prerequisite
180m
13-18 19-30
>31
11-27
>56
28-55
“Good” from LEED ND SLL Credit 5
Center for TOD Development 19-44
45-84
>85
30%
40%
>50%
LEED ND NPD Credit 8
80%
90%
>95%
LEED ND GIB Credit 8
80%
90%
>95%
MUD
25%
40%
>50%
LEED ND GIB Credit 14
5%
12.5%
>20%
LEED ND GIB Credit 11
80%
90%
100%
MUD
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F appendix F1 Sustainability Metrics for Kigali Objectives
Strategies
Measures
Level of Control in Current Zoning Code Control
Block Maximize warming effects of the sun in winBlock ter. Maximize shade in summer.
4
Passive Design
Optimize urban form strategies and building To reduce carbon passive design strateemission impact gies by utilizing existing of the project urban form to reduce project overall carbon footprint
Block
Maximize cross-ventilation access
Up to 10% additional building coverage bonus for use of Block sustainable building design technologies and construcBlock tion methods and/ or roof top communal facilities or roof gardens
Block
Increase connectivity of green system by integrating ecology and urban form
5
Ecological Preservation and Integration
Create opportunity of interconnected ecological areas within urban area
Establish substantial physical green conDistrict N/A nection between open spaces No disturbance of slopes over 20%
Minimize erosion to protect habitat and rePreserve existing duce stress on natural natural features water systems by preserving steep slopes
Parcel
1. Minimum of 15m in width with sufficient native species or adaptive plants to support stormwater management and/ or habtat conservation in the given context
appendix
Metrics
% Buildings arranged to shade each other and adjacent exterior spaces % of building groups located on the middle to upper part of the slope % of buildings rotated from cardinal axis to increase street shading % of buildings staggered for effective ventilation % of DU with Green edges of irrigated vegetation to cool incoming breezes A courtyard orientation 45o from the prevailing wind ( South ) maximizes both wind Design in the courtyard and crossDriver ventilation in the buildings. 40% of courtyards of over 100 sqm oriented at the specified angle Design NO. of open spaces connectDriver ed by a green corridor**
% of new construction on slope over 20%
Restore the slope area with native plants Parcel/ Design N/A % Restored Driver or adapted plants on District slopes over 20% Wetland Restoration & % Restored within 15m of District Preservation of sensitive land wetland Preservation and steep slopes under P4 Protected Areas/ 20m riparian Water body restoration % Restored within 30m of District buffer from wetlands waterbody and preservation
** Green Corridor
2. Maximum 10% impervious pavements
Steep slopes protected, threshold not defined
Priority Level
Topic
Target Better
Best
Data Source / Assumptions
30%
40%
>60%
Sun, Wind & Light p.83
30%
40%
>50%
Sun, Wind & Light p.88
30%
40%
>60%
Sun, Wind & Light p.103
30%
40%
>60%
Sun, Wind & Light p.107
30%
40%
>60%
Sun, Wind & Light p.132
30%
40%
>60%
Sun, Wind & Light p.207
2
3
>4
MUD
10%
5%
0%
“Good” from LEED ND SLL Credit 6
40%
60%
>80%
“Good” from LEED ND SLL Credit 6
100%
100%
100%
SLL Credit 7
100%
100%
100%
Good
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Objectives
Strategies
Measures
Establish a hierarchy of park types and scales
6
Access to Open Space
To provide open space access to all segments of resident and worker population
Provide hierarchy and distribution of open spaces so that walking distance to population is minimized
Designate Areas for Open Space Within/ Close to Homes
Facilitate Access to Open Space
7
Access to Local Services
To provide adequate local services to meet resident and visitor/worker needs
Level of Control in Current Zoning Code Control
District
N/A, size, scale, and use not defined
P1 Public Parks permissible in all zoning categories and Provide recreational conditional in P3 and P4 disfacilities close to work tricts, 5% of parcel minimum District and home to facilitate required for recreational uses physical activity in R3 and R4 zoning categories, NA for R1-R2 and commercial zoning
Provide private open spaces to applicable dwelling units
Priority Level
Topic
Distribute neighborhood level service within walking sheds to Distribute public community service facilievery occupant ties within reasonable District N/A walking distance of residents, visitors and workers
Good
Target Better
Best
Data Source / Assumptions
Types of activities: e.g. playground, bike trail, on-site program, workout stations, etc within parks
ASLA Sustainable Sites InitiaMin 2 tive Guide 3 types >5 types types lines & Performance Benchmarks Credit 6.6
% population within 400m walking distance to an open space per ha
90%
10-20% of parcel (depending on zoning category) reserved for landscaping/ 5% of parcel Parcel minimum required for recreational uses in R3 and R4 zoning categories
Provide pleasant walking experience while District N/A accessing an open space Small retail, convenience Distribute retail/food stores, and restaurants conservices within reasonditional in R1-R1A, R2-R4, able walking distances District I1-I2, P1-P2 and permissible of residents and in all Commercial categories workers except C5
Metrics
LEED NPD Credit 10
95%
100%
(Increase >21% from existing />31% requirement)
15%
20%
/25%
/30%
% of streets that have access Design open space through green Driver street connector***
10%
15%
20%
MUD
% population served by retail/ food services within 400m distance
70%
85%
100%
MUD
% population served by community service facilities within 400m distance
70%
85%
100%
MUD
% of parcel reserved for landscaping
*** Green Street Connector: 1. Minimum 40% tree canopy coverage or min 20% vegetation in ROW or utilizes green infrastructure such as bioswales and pervious pavement 2. Facilitates multimodal transit (min. of 3 modes of transit)
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F appendix F1 Sustainability Metrics for Kigali Objectives
Strategies Provide guidelines for place-making creation in the project
To improve physical and mental health and social capital to facilitate social networking, civic Establish landscape engagement, physical activity, standard for public realm and time spent outdoors
8
Place Making
Measures
Level of Control in Current Zoning Code Control
Provide hierarchy of quality civic and public Parcel/ space at community, N/A District district and neighborhood level Create an environment that makes it easy and intuitive for users to Parcel/ N/A (one signage per comorient themselves and District mercial tenant/building) navigate from place to place Provide outdoor seating areas with- a variety of seating within small defined spaces/ minimize noise to an Basement setbacks at 3m acceptable noise level/ min to ensure viable growth control adverse micro- Parcel of trees along lot boundaries climate (sun, shade, fronting roads wind)/ provide an aesthetic experience and access to vegetation/ unobstructed views of plant species
Increase connectivParcel 50% transparency for front Promote walking by ity between building walls in Residential categoproviding safe, appeal- façade and entries and ries, C3C, I1 ing and comfortable the public realm Parcel street environments that support public health Parcel
Parcel
No. of wayfinding components on site: Clear entrance/ view points and sight lines/ landmarks/ nodes/ hierarchy of pedestrian circulation/ orientation devices and systems,/ distinct areas/ maps/ brochures
Frontage zone is X meters (depending on building use) from parcel edge fronting a public right of way. When two uses meet, the more stringent setback rule takes precedence.
Good
90%
5
Target Better
Best
Data Source / Assumptions
95%
100%
LEED ND NPD Credit 9
>8
ASLA Sustainable Sites Initiative Guidelines & Performance Benchmarks Credit 6.5
ASLA Sustainable Sites Initiative Guidelines & Performance Benchmarks Credit 6.7
6
percent of seating for percent of total site users (Full-Time Equivalent (FTE) occupants and Temporary occupants
5%
10%
>20%
% of frontage zone built to
90%
95%
100m
Commercial/ Institutional Residential Over G+3
Maximum length of blank Design walls along sidewalks (withDriver out windows or doors) % of glazing on ground-level Design retail, services, and trade Driver uses Functional building entries at Design minimum average distances Driver along blocks
% shading achieved through Covered pedestrian walkways Design covered walkway and/ or required along main roads Driver street trees
**** Frontage Zone
appendix
% of existing DU and nonresidential buildings within 400m
Design Parking access from rear if Driver applicable
Block Improve quality of walking environment
Metrics
Design Driver Frontage Zone****
Parcel
Activate street life
Priority Level
Topic
0-3m 0-5m 45 setback from 4th floor onwards 40% of 30% of 25% of length length length or or 15m or 10m 8m
MUD
o
40%
50%
>60%
23m
20m
>15m
80%
90%
100%
40%
60%
>80%
LEED ND NPD Credit 1
LEED ND NPD Credit 14
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F2 Kigali Climate Analysis
Source: http://mesonet.agron.iastate.edu
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