RE_Building Transformation Guide

think make design form construct

transformation guide

Authors: Alina Barun

Kin Sun Tsang

Tomislav Martinovic

Summary of Master’s Thesis “ Transformation potential of existing building –Architectural design, environmental, social, and economic impact”

Department of Civil and Mechanical Engineering, study line Architectural Engineering

Supervisors:

Lotte Bjerregaard Jensen (Associate Professor)

Rune Andersen (PhD student in circular construction)

Submitted: 18.07.2022

full thesis can be found here

ABSTRACT

Construction industry accounts for almost 40% of CO2 emissions through construction and operation of buildings. While cuts in the use phase of the buildings is addressed through more strict energy efficiency requirements, that is not the case with the construction phase, and the emissions from the new construction are still increasing.

Thus, the main question this thesis is trying to answer is:

“Is demolishing of the existing buildings necessary and justifiable?”

A mapping of performance of existing buildings will be done to illustrate the transformation potential of them. It includes 3 pillars of sustainability and analyses, possible outcomes with arguing whether it is better to be transformed or demolished and replaced with a new building.

The analysis is tracking the whole life cycle of the buildings in the given area - existing building and its state, design process of the transformation to the new use, performance in the use phase, and comparing environmental impacts of these to a baseline scenario which is demolishing the existing, designing and construction of the new buildings.

general

Building transformation guide, also called RE , serves as a summary of steps while aproaching buidling renovation, transformation - changing the use. Instead of having a blank plot to start with, an existing building and its history needs to be analysed in search for opportunities to reuse already invested values. Furthermore, sustainability is defined through three pillars - environment, society and economy. Special atention was invested in order to take all three pillars into account, rather than focusing only on one, which unfortunately can be seen in a lot of occasions.

The guide goes through steps, findings and analyses done for the transformation of a three-story office building to a residential building mixed with commercial and communal spaces.

explanatory notes

general information about the topic, interesting facts

suggested checklist for solving specific problem or assessing the problem

toolkit suggests tools available on the market for solving specific task

important information/ what should be paid attention to

case study

PROBLEM STATEMRNT

Building at Vermundsgade 5 has been present in the local community life since 1934. It outlived many changes and undesirable events such as sabotage during II World War. Although according to SAVE registration, the building is on the low preservation list and therefore there is a high probability of it being demolished in upcomingyears. According to various analysis our team has done, it is evident that there is a transformation potential and the building could be preserved.

TABLE OF CONTENT

EXISTING STATE ANALYSIS

urban analysis building analysis

PROPOSED TRANSFORMATION urban concept building concept

EVALUATION environmental aspect social aspect economic aspect design choice

10 12 26 28 38 40 42 44

existing state analysis

urban analysis

Every new project starts with finding all existing information about the buidling and its surroundings. Starting from a wider perspective different type of data could be collected. They could be split into two categories; soft data looks at site conditions that can be changed and hard data focuses on rather concrete elements such as dimensions, utility locations, site boundary etc. Integral part of analysis is are legal requirements such as max built percentage, maximum height of the building, possible restrictions about roof type or materials selection. All findings will provide a solid base for future design development and will support decision making in various fields.

• neighbourhood context

• zoning and size

• legislations and future development plan

• sensory - noise, views (time dependant)

• physical features of the site: trees, water, topography

• circulation through the daypedestrian, vehicle

• legal requirements

• zoning

• limits (max. height, footprint,...)

• local plan

• map analysis

• local plans

• site visits

• GIS analysis

• Space Syntax

The neighbourhood in question for this case was Haraldsgadekvartet, situated in Copenhagen, Nørrebro. To understand the urban context, it is necessary to look into points of interest in close proximity of the location, such as schools, shops, public transportation hubs, etc. In addition, GIS analysis helped with analysing materiality of the area, which can support the decisions regarding reclamation and reuse of products and materials.

residential buidlings ( 51 % ) offices ( 17 % ) production industry ( 8 % )

GIS ANALYSIS

SUN PATH ANALYSIS

building analysis

BUILDING ANALYSIS

After understanding the area and neighborhood the analysis of the buidling can proceed. The on site inspection will provide good start for overall picture - facade materials, level of maintenance, possible structural system. From available documentation more information can be read - history and use of the buidling, detailed dimensions and structural system. This serves as a baseline for creating existing 3D model for progressing with further various analysis and calculations. Following pages present selected analysis, that were crucial for the study case, with short description accompanied with figures or tables for better visual communication. Selected steps serve as an example and one of the ways how to access the problem when looking at the possibility of transformation of existing buidling stocks.

1934

• history & building development

• use of the building

• material analysis (toxic materials)

• energy performance of the building

• daylihgt analysis

• transfomration potential

• structural analysis

1947

Phase 1.1

Main building is reinforced after the sabotage on 11. September 1943

Phase 2

Two part annex building was erected perpendicular to existing one and served as storage and additional factory space

1949

1952

Phase 3

An extra floor was built on top f main building and external elevator was added on the southern facade

12 • if possible, do a site visit and look for resources from the occupants

Initially built as K.A. Hartmanns machine facotry in 1934, buidling went through many extensions and renovations. Final major changes were made in 1997 where it got its present form. Currently building is occupied by Hans Knudsen Institute, a non-profit organisation that aims help people with special needs. Part of it serves as a workshop space, part as edicational space and the rest is dedicated to offices. Timeline is presented below. Building is situated in Haraldsgadekvartet in northern Nørrebro. The are is undergoing many transformation to ensure social, physical and cultural development. Initialy industrialised zone today serve as home for many inhabitants.

RISK ASPECTS

Additional consideration for any alterations to the building is the layer of Eternit (cement-fiber board) in the façade. According to the Energy Label Report and archival drawings of the building, there are existing Eternit panels in the façade, behind the layer of aluminum cladding. Eternit is an alternative name for cement-fiber board, which is a composite material made of cement and cellulose fibers that exhibits excellent durability, moisture absorbency and thermal properties. . However, Eternit or in general cement-fiber board is considered to consist of asbestos before the EUwide banning came out in 1999 and was fully in force in 2005.

Phase 4

Annexed building was changed into one object with change of use to office.

1989

1977

Phase 5

Main building was transformed into office building. An internal elevator was on the southern façade together with the staircase

13 HISTORY & USE

Phase 6

The façade of the main building is renovated and cladded with aluminum panels.

2004

Phase 6.1

Main building was connected to districted heating

1997

building analysis

EMBEDDED VALUES

Every year the world consumes millions of tons of recourses yearly and also produces millions of tons of wastes in different types. Waste is a huge source of pollution which of course cannot be denied, but on the other hand it could be seen as a highly potential resource for reuse in various ways.

Analysis for embedded values played an important role in resource-based thinking design proposals. Looking at the amount of materials, their price and impacts , it underlines the importance of circular construction. This approach will help to reduce the impacts, minimise construction waste, bring the uniqueness to the materials as they can be used in a new, innovative way, as well as keeping the “embedded culture” and story of the building.

circular construction

REDUCE REUSE RECYCLE

•

3D modeling soft wares that allow quan tity takeouts (BIM authoring tools)

• LCA and LCC calculation software

• the accuracy of the analysis depends on the data availability

• look for public archive drawings, construction drawings, maintainance records, etc.

MATERIALS

In the case study the amount of concrete was estimated to 2743 tonnes with equivavelent of 2993 tonnes of CO2. Together with steel (reinforcement) they are two the most CO2 intensive materials. Therefore reusing as much as possible was one of the main tactics. Aluminium cladding as well higly contribute to CO2 emissions and therefore is one of the first materials on the reuse list. Windws, doors and roof trusses can be reused in many different ways. Especially if the condition is good. They can be dismounted and used separately (glass & window frame) or reused as the whole component. Lastly, insulation was determined with the potential of being reused. If the insulation is installed in the form of battes, the removal and reuse is even more user-frie

REUSE OPTIONS

how/ where obstacles

GWP (first educa tional guess)

concrete structures high

roof trusses aluminium cladding

crushing rein forced concrete

reuse/ recycle low

storage & transport

new roof construction high

cladding/ rofing

asbestos removal

green house/ partition walls medium

roof insulation

dismouting & cleaning

medium

keeping properties

15 doors/ windows insulation (walls)

Following charts represent amount of materials, embedded CO2, and the price

building analysis

ENERGY

Energy consumption is always a hot topic in building design, and it is the same in transformation project! Huge usage of energy makes it contributing a lot to both cost and carbon emmision, thus, it is essential to carry out a screening of energy performance of the existing building prior to the start of transformation design. Here are some suggested aspects specific to a transformation project that one should look at, along with some useful tools.

• Building envelope

• Energy consumption

• Form of energy source

• Ubakus (simple u-value calculation)

• IDA ICE / BE18 (overall energy simulations)

• what is the average u-value?

• is it possible that it is not well-insulated?

• what is the form of energy?

• Is the building heatd by 1) district heating, 2) gas boiler, 3) electricity or 4) heatpump?

• Is it possible to install solar PV cells or solar heating panel? try it out!

ubakus u-value calculator

ENERGY

What we look for here is the potential savings of 1) energy, 2) carbon emission and 3) cost by inmproving the building. An educated estimations of where to improve is generally helpful, but if requires evidence to support the decision. A threshold of the saving breakeven before 3/4 life time is suggested by BR18 and set as a indicator for a renovation actions worth carrying.

In this case study, a Energy Label Report for Vermundsgade 5 was issued in 2015, which incorporated the necessary energy audit and determined the performance of the building, the potential energy saving actions and the expected new energy label level after implementing the actions. The building is said to be able to improve from Level D to Level C.

The feasibility of actions such as switching the source of energy, improving thermal envelope etc. are checked in regards to both environmental and economic concerns.

POTENTIAL SAVINGS ACTIONS SUGGESTED BY ENERGY LABEL REPORT

DKK district heating (MWh) EL (kWH) CO2 (ton) investment (DKK)

replacing doors 800 0,65 164 0.2 10,400

replacing windows 31,400 26.95 6736 8.27 622,000

Annex - district heat ing 79,000 -58.99 58994 30.80 720,000

pumps insulations 3,300 5.07 -48 0.68 1,500

pumps replacement 8,300 / 4107 2.72 40,000

new circulation pumps 2,100 1.59 518 0.57 10,000

LED light 3,300 -0.78 1864 1.13 6,200

toilets motion detec tion 600 -0.18 347 0.2 4,100

solar cells instalation total

7,100 135,900

/ -25.69

4649 77331

3.08 47.65

19 97,200 1,511,400

building analysis

TRANSFORMATION POTENTIAL

Transformation Potential indicates whether the existing building is good and easy to be transformed, and which building typologies is the best to be transfromed to. There are not many available tools in the industry at the moment, and they are under development. Some tools are still very useful in visualising the Transformation Potential of the existing building.

• Transformation Potential Tool (TPT)

• Conversion Meter

• does the building has a high transformation potential?

• which scenario would perform the best?

Transformation Potential Tool

Score of TPT spans across 1-9, where 1 being the highest and 9 being the lowest. Here the result for Vermundsgade 5 is 3.3 for office scenario nad 3.7 for both multi-storey and education institute. That indicaes a medium close to high potential to transform the building into all three scenarios, with office being the best option.

Transformation Potential Score

Transformation Potential Score for the For Main Indicators (Assessed from 1 9, with 1 being the best value)

LIFE CYCLE ANALYSIS

Life Cycle Analysis include a lot of aspects, such as environmental, social and economic. Besides the mostly referred one which is environmental, all 3 sustainaility pillars should also be looked at in the life cycle perspective and to determine a good solution especially because building has a long lifetime and its performance in later stage should be taken into consideration.

• One Click LCA

• OpenLCA

• LCAbyg

• SimaPro

• mapping is correct?

• suitable EPDs?

• suitable energy consumption

• correct selection of lifecycle stages?

• most contributing material?

• kg CO2-eq (and other impact categories)

• most contributing material?

• most contributing lifecycle stage?

• how far is it compared to the Danish building CO2e limit

• LCCbyg

• Sigma Estimates

• Molio Prisdata

• correct mapping?

• correct discount rate and price development?

• what uncertaintities are there?

• Potential rent

• Net Present Value / Residual Value

• Discount rate / Price development

• which cost items cost the most?

• which lifecycle stage cost the most?

• would the cost of transformation out weight the income?

• when would the investment achieve breakeven?

LCA LCC

building analysis

DAYLIGHT

The access to daylight has been proven by numbers of cognitive studies to be critical to healthy urban environment and the well-being of occupant comfort, therefore, huge efforts from both the academic and the industry have been put to create assessing metrics to guide the design to optimise daylight availability. Among all, the most widely adapted metrics include Daylight Factor (DF), Daylight Autonomy (DA), Useful Daylight Illuminance (UDI).

STRUCTURE

• Daylight Autonomy (DA)

• Useful Daylight Autonomy (UDI)

• Daylight Factor (DF)

• Climate Studio

• Velux Daylight Visualizer

• Daysim

Structural capacity is crucial for transformation project, especially if it considers change of use such as this one. Original structural design procedure from 1934 is definitely outdated, hence it was decided to do a brief check with new loads according to relevant standards. The level of conservativeness depends on the level of knowledge about the structure. In this case, cross-sections and reinforcements were available from the archived drawings, and upon visiting the site, it was concluded that the building is properly maintained, but because of the age of the building, more detailed studies are needed if the project is to advance to construction.

• on site evaluation

• relevant standards

• SCIA

• EXCEL (or any other suitable calculation software)

The simulation is carried out with Rhino 7 and the built-in tool Climate Studio, with the building model imported from Revit using Revit.inside.Rhino plugin. The figures below illustrate the Daylight Factor results, where yellow being the highest side and purple being the lowest side. The average DF for the whole building is 3.73%, which is higher than the recommended value. The building, in its existing state, is well-lit with sufficient daylight.

ground

DF=3.5 %

Presentation of floor plans with light analysis

STRUCTURE

New loads have to applied according to the new use. Latest trends are to transform old industrial buildings to residential, commercial and/or office use, which usually doesn’t pose a structural problem since the new loads are lower than design loads for industrial buildings

DF=3.97 %

DF=3.92 %

Floor slabs, along with primary and secondary beams, were recalculated and proved to pass the check with little to none improvements needed. Unfortunately, the building doesn’t seem to be suitable for additional floors. As previosly mentioned, concrete and reinforcement steel have a lot of embedded impacts and costs, and this outcome is extremely beneficial since the structure, where majority of those materials are, can be reused.

urban concept

In order to fit the work done into a larger scope of transformations that are planned in the area, urban concept was developed. The main idea is to open the central part of the plot and clear the secondary buildings with low preservation value and in bad state. That will give the possibility to create a so called “green oasis” with playgrounds for the community inhabitants. Enabling access through new gates from streets –Titangade, Vermundsgade and Sigursgade – will provide better pedestrian circulation and courtyard access.

demolished secondary buidlings connection with surroundings

At the material level, the concept will include recycling in varying degrees – from preservation, renovation, and transformation of selected buildings to materials recycling on the site whenever the building is demolished. Materials should be seen as potential building materials and elements of future design, rather than waste. Those materials could be used for new facades, secondary buildings, surfaces, or furniture in urban spaces.

Following 12 rules of quality by Gehl we propose a good quality public space that will encourage pedestrians to spend time in the space, move around and experience it. The courtyard will bring people of different ages and interests together, creating a pleasant space to spend free time with friends and family. The new design will consist of basketball court, two pentaquin fields, playground for younger kids and a skate park. The variety of activities will encourage social engagement between the people. Great number of benches will be placed along with newly planted trees, creating shadows during hot sunny days. A relaxed meeting place will ensure enjoyment and positive sense experience. Several brick walls from the old buildings will be conserved and used as partial separation keeping an authentic touch and identity of local character.

building concept

The existing state analysis has provided us with valuable information on what is available in the building, along with embedded carbon and economic value. In order to lower the impacts, the design had to incorporate those elements. Following the idea of a resource-driven design, we listed the most impactful materials and elements, as well as some that proved flexible from a construction point of view.

TRANSFORMATION

According to the SAVE registration the building has low preservation status and very likely would be demolished in upcoming years when the surrounded area would be transformed. Although, according to the carried-out analysis from different perspectives, it has very high transformation potential. Particularly, transformation potential analysis demonstrated that the most suitable option would be transformation into residential use.

USE

Comparing to the existing building the main change is, the change to the different use – office to residential building. Based on that, two types of housing were furthered developed:

• DORMITORY – where the main users are expected to be younger generation including students looking for smaller, affordable housing

• APARTMENTS – along with young families and elderly people, the layout provides bigger apartments for family with kids.

In addition two control scenarios will be considered. First, considering the building as it is, for another 50 years. Second, scenarios is a newly constructed building. It is theoretical one, meaning the values used for evaluation are based upon reference data from literature and/or educated guesses.

With the change of use, the necessity for some new facilities was considered. That result into using the ground floor area as a commercial space with several proposed businesses such as cafeteria, bakery and grocery store. That can help with financial feasibility and attract non-residents to the building. Additionally, it positively effect plinth, that is inviting pedestrians to experience the building, enjoy morning coffee with freshly baked pastries and bring the community together.

FAÇADE

During the transformation process the driving force was to do reuse as much as possible. New, updated façade is reusing the existing panels. To bring it a fresh touch, panels are being cleaned and rearranged in a new way. The position of the existing windows is kept the same with the new ones following the existing grid. Both scenarios include balconies that break the façade into dynamic way providing the visual change and connecting inhabitants with outdoor spaces.

COURTYARD

Inner courtyard will be equiped with new outdoor furniture placed along the facades with plant boxes with trees. A lot of them are for example made from the reused wood that was extracted from the building.

New outside staircase is added to access the flat roof of the Annex building where additional common space is located. A greenhouse from reused windows on the flat roof. It serves as a place for residents or workers to relax, play some board games or organise common events.

building concept

Apartment scenario is focusing on accommodating family of different sizes. It could be young or elderly couple or family with one or more children. The proposed design accommodates 20 apartments varying in size from 40 to 90 m² over two floors. Apartments are almost the same on both floors with smaller changes of balcony placement to create a more dynamic façade.

Apartments are design around three communication cores. Corner building entrances lead to the three apartments on each side and middle cores provide access to 4 more apartments on first and second floors.

The rent for the apartments varies depending on the size and is calculated to be between 6000 kr. and 12500 kr. The price is calculated based on average data across Denmark and do not include utilities.

APARTMENTS

Daylight Authonomy analysis show that the main living area could achieve 300lux 50% of daylit hour. Darker area are used mainly for bathrooms, kitchens, entrance and storage. As a result of initial corridor removal in the middle of the building, more light can penetrate deeper into the apartments.

DORMITORY

In dormitory scenario spaces are divided into private –studio apartments and common spaces that are shared between the residents. In total the proposal offers 29 apartments for new young families or students. Twenty-five one-person studios have on average 21 m², access to the private balcony, own bathroom and a room with kitchen corner.

A fully equipped kitchen is located on the first floor and can provide seating for 20 -25 people. The central part is allocated for table football, board games or just relaxing. From the first floor, close to the central elevator it is possible to access the flat roof of the Annex building with additional seating as part of the green house.

The rent of 21 m² one-persone studio is calculated to be rented out for 3600 DKK and the 40 m² can be expected to cost around 6900 DKK.

For this scenario it was proposed to open part of the roof with big glass windows placed between rafters as can be seen on the render to the right. It allows sunlight better penetrate the space and bring the feeling of even spacious room.

Daylight Authonomy analysis show that the common area and apartments could achieve 300lux 50% of daylit hour. Darker area are used mainly for bathrooms and storage. With addition of roof windows, the common area is very well lit.

Rendering of the common space with roof windows

With Phasing options in Revit many different visuals can be made. Two models show exploaded view of the building. Picture on the left shows the existing state, in grey, and all demolished parts, in red, for Dormitory scenario per floor. Picture on the right presents new proposed design

learn more about Revit phasing, chek it out!

Common kitchen with seating area

Example of one person studio apartment with balcony

Common spaces with new roof windows

View of inner courtyard with green house on the roof of annex building

Facade view from Vermundsgade street

View of inner courtyard with green house on the roof of annex building

evaluation

environmental

LCA STUDY

From January 2023, new buildings in Denmark with more than 1000 sqm have to prove that their GWP impacts are lower than 12 kg CO2 eq/sqm/yr. This decision comes as a part of a new Danish National Strategy for Sustainable Construction, aiming at reducing carbon emissions by 70%, compared to 1990 levels. This is a major milestone on the road towards environmentally friendly construction industry, and it is of great importance to put all projects in that context.

LCA study was made for this case as well, comparing the designed scenarios and control scenarios. BIM once again played an important role, enabling the utilisation of information from BIM model through a plugin.

Designed scenarios were transformation of the existing buildings to an apartment building or a dormitory, while control scenarios were “Do nothing” - representing the operation of the building as it is for another 50 years; and a completely new building represented by the limits from the beforementioned National Strategy.

Global warming [kg

Transformation to

16.36

Danish National Strategy for sustainable construction BUILD report median for 50 years reference period 5.39

9.54

• Comparing reults from different LCA studies is a “slippery slope”. For example, LCA study made in this case uses impact profile from previous years, while the ones used in the chosen reference analysis (BUILD report), and for defining the limit in the National Strategy, uses projected impact profile which additionally decrease the estimated impacts. Until the discrecpancies between the tools are dealt with, being aware of this is of extreme importance.

• One Click LCA

• EN 15978, ISO 14040, ISO 14044

• EXCEL

38 • Use EPDs that are covering average values, rather than a product specific ones, whenever possible.

BUILD report median material phase for 50 years reference period

to dormitory

nothing

Construction Materials Maintenance and material replacement Energy use Waste processing Waste disposal

Global warming [kg CO ₂ e / m² / yr]

RESULTS

16.36

Danish National Strategy for sustainable construction

BUILD report median for 50 years reference period9.41 9.54

BUILD report median material phase for 50 years reference period

Results are showing that in this case, transformed existing building would emitt less carbon over their whole life cycle than a completely new building would, with close to no difference between the two transformation scenarios.

From the results chart, it can be seen that operational energy is making the majority of impacts, meaning that improvements to thermal envelope are absolutely necessary in this kind of projects in order to reduce energy use in the operational stage of the building. The proposed transformations included the improvements proposed in the energy label, meaning energy class C. Improving it to energy class A 2020 would additionaly improve the results.

Even more striking difference can be observed in the material phase, where transforming the existing building would emitt 75% less carbon than a construction of a new building . This can be seen as a direct outcome of resource-based design approach, which makes the best efforts to reuse as much as possible, without compromising usual principles of architectural design and quality of space.

39 So, transforming this building instead of building a new one same size would save approx. 656 tonnes of CO2 . This is the same as doing a road trip with a diesel car , almost four million kilometers long. In order to store that amount of CO2 , forest a size of DTU campus is needed, growing for at least three years.

Transformation to apartments

Transformation to dormitory Do nothing

Construction Materials Maintenance and material replacement Energy use Waste processing Waste disposal

Often, there is lack in transparency on what social sustainability is and what is the best way to approach it and measure. But based on research studies this absence of certainty arises due to hight complexity of the social dimension of sustainability. This forces researchers to develop case specific and place specific formulation.

As there is no single framework applicable to all disciplines and scales, the evaluation framework should identify relevant indicators and measures based on the goal and scope of the study.

• Selected tool in this project has 5 main themes that are followed by number of criteria further divided into indicators. They derived from theoretical studies along with review of existing tools such as Renobuilt, Telos and DGNB . The themes are describesd as followed:

Equity/Quality of life – the criteria within this theme relate to the fundamental needs of people, existential needs, such as the ability to choose and influence your own environment.

Connection/Accessibility – theme is focused on the ability of the built environment to strengthen interconnectedness by providing necessary facilities

Pride and sense of place – adapted from ReBo model, it deals with internal and external opinion and factors (mostly physical) that influences them

Social cohesion – adapted from ReBo model, theme approaches mix/diversity, stability, and networks (as opposed to the physical prerequisites included within connection/accessibility)

Democracy – this theme weight user possibilities in communication and participation through the design process check out more about Social sustainability tool

RESULTS

According to the selected tool, the final results are presented in the form of diagram below. Overall, the change of use from offices into the residential building has scored better across 6 out of 8 selected criteria with dormitory scenario being the best choice.

Dormitory scenario scored the highest with the most even distribution of points across criteria with the final score 8. Comparing to the previous scenario it performs better across three criteria – Urban connection, Social Diversity and Services/jobs

Apartment scenario scored 7,6 points. Category Freedom of choice has the highest score as it offers various options of the apartment size and type (including apartments for residents with special needs).

Do Nothing scenari has 2 out of 8 indicators, namely Affordability and Freedom of choice, that received score lower than 4 and according to the pre-set weight are not included in the final diagram. It is important to mentioned that criterion Affordability was not assessed, as it is related to the apartment characteristics and do not relate to office use. This scenario performed the worst with a score 5.4.

economic

When assessing the economic performance of the design proposals, a hotspot analysis was made to evaluate the influence of the building typologies, as well as a detail comparative study for all the proposed scenarios. The aim of the hotspot analysis is to visualise how thebuilding typologies would affect the economic performance of the same building. Office building, domitory and apartment buildings are put into comparison.

Following up is the case specific analysis, parameters for each scenario are made according to the use in real life:

1) Existing mixed use and transfromation cases would have exempted aquisition cost

2) transformation cases incorporate costs for changes and extra consultation fee

3) new building case only has 75% of the built area due to the limit from Local Plan

4) both tranformation and new building cases incorporate annual savings from potential energy saving actions

RESULTS

Name Existing mixed use Dormitory Residential Acquisition 23.988.340 20.953.359 22.501.196

Maintenance 5.616.556 5.032.056 5.276.269

Replacement 4.450.081 4.023.518 4.263.059

Supply 21.197.966 25.389.547 26.355.050

Cleaning 16.680.393 17.924.629 18.059.202

Recurring income 85.335.438 77.705.977 81.197.376

Net present value 13.402.103 4.382.868 4.742.600

Existing mixed use, which consist of mainly office use and educational institute could be the most profitable over the whole lifetime of the building, with a high income and low utilities use.

5 Economic Principles of Sustainable Construction

1) Value for money

2) Maximum output with minimum input

3) Integration of short term return and long term benefits

4) Stakeholder partnerships

5) Human quality of life: from asset to services

COST EFFICIENCY

design choice

SCORE

To adress all three pillars of sustainability, a simple yet effective system was needed to put the designs against each other and control scenarios.

First step was to evaluate all of the developed designs and control scenarios and assign them impact points ranging 1-5. As we are talking about the impacts, the logic behind it is that “less is better”. The points are assigned considering how designs and scenarios preform compared to each other, meaning that there is no absoulte scale allowing for comparison with other buildings and projects. This might change with development of absolute sustainability as a field.

Second step is to weight the impact points. Weights applied in this case were 0.8 for environmental aspects, 1.0 for social aspects, and 1.2 for economic aspects. The thinking behind this was to avoid “money doing the talk”. A lot of times projects with good environmental and social consciousness are halted because they will not result in as big financial profit as some other alternatives would. Weights like this try to “award” designs for performing well environmentally and socially, while still taking into account the economics of the project as it is an important driver.

& DISCUSSION

Majority of the buildings that we are using currently, and the ones that we are going to be using in the future, are already built. Adressing this existing stock is of great importance if we want to improve the quality of those spaces and the quality of life of its occupants. Even more important, improving and building upon the existing stock is directly avoiding new construction that is supposed to replace obsolete buildings. Works such as this prove that buildings have more than one lifespan, and just because it is obsolete from one point of view, it does not mean the whole building is good for scrap.

Furthermore, the design of transformations needs to be approached with special care and principles in mind. This tends to look intimidating at first, but it is especially rewarding because the work done is embedded in the urban fabric and the way cities and neighbourhoods work. Up until recently, additional constraints that come with transformation projects were looked as restraining factors, but once they are analysed and properly understood, they for sure start serving as a tool, and should be embraced.

FINAL TAKEOUTS

Alternatives considering the transformation of the existing buildings were found to make smallest impacts according to the LCA, with little to no difference depending on the scope chosen, both getting 1 impact point. “Do nothing” alternative makes the largest impact due to insufficient thermal performance which drives the increased energy use in the use stage, thus getting 5 impact points. Lastly, new construction improves on that point, but has additional impacts from the material stage, which is avoided in the transformation alternatives, and gets 3 impact points.

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Different criteria were evaluated to understand and “put a number” on social aspect of sustainability. Comparing to other two pillars of sustainability the assessment is not that straightforward as many aspects of wellbeing seems to be rather subjective and even wellbeing doesn’t have one agreed definition. The difference between scenarios were very little but firstly, looking strictly at social impact the Dormitory scenario performed the best and received 1 impact point, the Apartments received 2 points, and Do Nothing is considered as the least favourable option with 5 impact points. As previously mentioned, new construction is expected to address social aspects to a respectable degree, so that scenario also got 2 impact points.

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The two calculation sets show that the existing mixed use, i.e. do-nothing, has the highest profitability, thus 1 impact point is given. That follows by the two transformation scenarios which are very similar to each other, but the residential case is still slightly better, 3 and 2 impact points are thus given to dormitory and residential respectively. The new construction scenario is way lower than the others, due to the low rentable area constrained by the local plan, an impact point of 5 is given to reflect the result.

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ALINA BARUN ARCHITECTURAL ENGINEER

Architectural design with focus on social aspect of sustainability and urban development abarun97@gmail.com

TOMISLAV MARTINOV iĆ ARCHITECTURAL ENGINEER

Building design with focus on environmental aspect of sustainability tomislavmartinovic001@gmail.com

KINSUN TSANG ARCHITECTURAL ENGINEER

Building design with focus on energy, daylight and economic aspect of sustainability kinsuntsang.95@gmail.com

Vandkunsten Architects