Catching Daylight: Improving Natural Illumination Levels in residential buildings in Amman, Jordan

Research course: Research methods by Dr. Abdulsalam A. Alshboul

University Of Jordan – Department Of Architecture Master’s degree of architecture Research Methods 2018 Dr. Abdulsalam A. Alshboul

Diana Omar Al-Atrash 8180130

Research course: Research methods by Dr. Abdulsalam A. Alshboul

Catching Daylight: Improving Natural Illumination Levels in residential buildings in Amman, Jordan Diana Al-Atrash Architecture Engineering Department, the University of Jordan, Amman 11942 - Jordan

Abstract The urban environment can cause obstruction of the sky thereby affecting sunlight and daylight availability on the building fenestration and also further inside the building.

Daylight is an important part when designing a building. It is vital to have a good level of daylight in rooms where people stay for extended periods of time since it has been proven that a lack of daylight affects people’s health and wellbeing in a negative way. This should lead to the setting up of mandatory regulations on both urban and building design levels and the minimum program requirements (MPRs) that make a project appropriate to pursue LEED certification.

This paper aims to predict the relationship between buildings setbacks and buildings heights according to the climate, in order to find the best angle of obstruction. Through analytical case study at Amman, Jordan, it tries to investigate current building regulations of greater Amman municipality (gam), according to climate characteristics. The study will ensure that distances between apartment blocks and its heights in Amman have to be set up according to climatic change in summer and winter. To achieve the goal of this study, the current buildings setbacks regulations in Jordan have to be modified according to climate change.

Keywords: Setbacks, solar position, angle of obstruction, daylight, energy saving, LEED certification.

Introduction In the present day, the dwelling and habitat are invariably linked to making buildings as comfortable and convenient possible all over the world. The building sector is growing at a rapid pace by investing 30–40% of total global basic resources. The present day buildings have become the third largest consumer of fossil energy after industry and agriculture.

Daylight use in buildings has a positive impact on the users comfort, well-being, and productivity. Replacing artificial lighting with day lighting is energy-efficient and also has a positive impact on peak loads and HVAC consumption. However, besides the structure itself, the urban environment in which the building is located has an influence on energy performance. The urban environment can cause obstruction of the sky thereby affecting sunlight and daylight availability on the building fenestration and also further inside the building.

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

But most architects design their buildings without any concern to site forces (location, orientation, nature or climate).that leads to produce uniform buildings without any relation to its surroundings therefore these kind of design will effect on human comfort, behavior and health. The creative designer who can achieve human comfort through smart solutions which emerged from building site and climate.

Jordan has witnessed a large urban growth in cities where new apartment blocks have been constructed. In general, investors in Jordan are keen to invest in new apartment blocks in different locations in Amman fulfilling local demands for the new blocks.

However, this situation creates new problems in terms of solar accessibility and solar rights. It directly reflects on energy saving issues in these buildings, and eventually affects the overall energy consumption nationwide. Legislation should guarantee a certain amount of day lighting access for each building. In many countries there are land usage laws, which define the occupation percentage, building heights and easements.

Design Architects and interior designers often use daylighting as one of design elements. Good daylighting requires attention to both qualitative and quantitative aspects of design.[7] Qualitative Utilizing natural light is one of the design aspects in architecture; In 1929, the French architect, Le Corbusier said that "The history of architectural material... has been the endless struggle for light... in other words, the history of windows." As he emphasized in his architecture (such as Notre Dame du Haut), daylighting has been a major architectural design elements. Not only the aesthetic aspects, the impact of daylighting on human health and work performance is also considered as qualitative daylighting. The current studies show that lighting conditions in workplaces contribute to a variety of factors related to work satisfaction, productivity and well-being and significantly higher visual acceptance scores under daylighting than electrical lighting. Studies have also shown that light has a direct effect on human health because of the way it influences the .

Quantitative A well daylit space needs both adequate lighting levels and light that is well distributed.

In the current building industry, daylighting is considered a building performance measure in green building certification programs such as LEED. Illumination Engineering Society (IES) and the society of Light and Lighting (SLL) provide illuminance recommendation for each space type. How much daylighting contributes to the recommended lighting level determines daylighting performance of a building. There are two metrics that IES has approved to evaluate daylighting performance: Spatial Daylight Autonomy (sDA) and Annual Sunlight Exposure (ASE). sDA is a metric describing annual sufficiency of ambient daylight levels in interior environments.

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

What are setbacks?

Setbacks are building restrictions imposed on property owners. Local governments create setbacks through ordinances and Building Codes, usually for reasons of public policy such as safety, privacy, and environmental protection. Building setback has been defined by building regulation policy in the city of Amman, code No(67)for the year 1979; as buildings yard which are unallowable to construct within, where construction line and land boundaries from all sides [1] .

Table 1 Required building setbacks in GAM regulations for residential zones. (Source: Greater Amman Municipality, GAM, 2006).

Table 2 The minimum allowable plot areas for residential zone categories in Greater Amman region.

Why daylighting?

It has been proven that providing buildings with natural light is necessary for good vision and visual comfort; it also offers comforting space for building occupants and Schuster [2]. Humans prefer natural illumination due to their preference of natural substances and because it consists of a balanced spectrum of color [3].

Daylighting creates a healthy environment inside buildings; it improves psychological health and the general well-being of buildings' occupants [4].

Regulations in Jordan and solar rights The problem of solar rights in Jordan exists in the developed areas as they have relatively high blocks compared to traditional buildings. Vernacular architecture normally does not undergo the same regulations applied in developed areas. Vernacular buildings in Jordan 3

Research course: Research methods by Dr. Abdulsalam A. Alshboul

are not normally higher than two stories; which does not affect the solar envelope of buildings. The integration between vernacular architecture and respecting solar rights is a key generator of urban form. Vernacular architecture, in fact, is a good example for providing solar access for buildings. However, this study focuses on the developed areas in Amman, which have the problems of solar rights. Greater Amman building regulations were set up to organize and control building clustering within urban design criteria in the city. These regulations control setbacks and distances in land plots, construction of buildings, and urban clusters in Amman. Architects, designers, and contractors are guided by these regulations. Basically, these regulations deal with land use categories, residential zones, setbacks, overall ratios of built areas, and maximum residential block heights [5].

Literature Review Daylight has been utilized as a design element in buildings throughout history. One of the main reasons for using daylight in recent years is its benefit in reducing energy consumption through its use as a main or secondary illumination source in order to replace the use of electrical lighting.

The urban environment can cause obstruction of the sky thereby affecting sunlight and daylight availability on the building fenestration and also further inside the building. For Ăœnver the sky obstruction is characterized as one of the main influences on the natural light in an interior space [6].

Hopkinson proposed a graphic method based on the geometric relationship between building height and spacing. The objective of this method is an acceptable level of daylighting in indoor environments, while controlling the amount of sky obstruction [7].

Ng has conducted studies of the city of Hong Kong using different urban scenarios in order to introduce new alternatives that would provide access to daylight in the context of a highrise urban environment [8]. several scholars have raised concerns about the need for serious examinations of climate change integrated with the planning and urban design process, the only work in urban planning that directly addresses the design of cities in relation to climate change disasters is that of Donald Geis (2000). Geisâ€&#x; work consists of a general urban design, planning, and local government guideline to design such communities, although more detailed and graphic urban design guidelines that may serve as blueprints for designing disaster resistant communities are still missing in his published work [9].

Distances and setbacks between apartment blocks imply the importance of urban density and urban compactness in respecting solar rights and solar accessibility. Within this context, solar design principles have not been re-examined regarding their relevance to the climatic conditions.

Many architects have handled the concept of solar design over the past decades. In 1920, Klein put forward an interesting urban guide for the optimization of land use, density, insolation, and ventilation in housing. Likewise, Le Corbusier developed his ideas for the

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

Ville Radieuse considering the Heliothermic axis as it represents the most desirable orientation that accounts for solar access [10].

In Dr. Abdulsalam A. Alshboul and Dr. Hussain H. Alzoubi research about Low energy architecture and solar rights, the study discussed solar rights and solar envelope in order to evaluate the solar rights in apartment buildings; however the study focused on the developed areas in Amman. The study asses the relationship between setback and building geometry to ensure adequate solar radiation on building facades [11].

In Dr.Khaled Al Omari and Arch.Hind Alshoubaki research about Effects of Setbacks on Solar Accessibility In Amman, Jordan, the study discussed the relationship between building height and setback to achieve the targeted insolation percentage [12].

Statement of the problem The building sector plays a major role in the world’s total energy consumption. Buildings are responsible for approximately 40% of the total world annual energy consumption, and that considered as great challenge for designers, urban planners and policy makers.

This research try to find a mechanism to reduce the impact of hazardous planning through analytical study for current setbacks regulations and integrate it with LEED certificate requirements [13]. and reform them according to climatic parameters in order to enhance sustainability in urban planning.

Statement of purpose Many studies had examined effective procedures to ensure more ecologically outcomes in the planning process. But this research try to give a radical solutions by reconstructing new regulations based on environmental factors of the specific neighborhood.

Methods and materials The methodology of this study consists of the following: Measuring the angle of obstruction in different cases: The effect of opposite close buildings and the floor level: Dense urban fabric decreases internal daylighting to a considerable degree, at lower floors in particular, due to shading from neighboring buildings that decreases natural illumination inside the room. If the external surface reflectance of the opposite close building is low, internal daylighting levels decrease and increasing the reflectance of the opposite building's exterior surfaces will increase DF inside the rooms with side windows, especially at lower floors.

In order to understand deeply the effect of climate on building design and regulations and to improve that the angle of the obstacle (the vertical angle between the solar beam of the top of the building A and the horizontal plane shall not exceed 70% of the residential buildings.

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

Based on the equation : tan đ?œƒ = đ?‘†=

đ??ť đ?‘†

đ??ť cos đ?œ‘ tan đ?›˝

đ??ť đ?œƒ = arctan [ ] đ?‘† Where đ?œƒ: angle of obstruction; S: setback; H: height; đ?›˝: solar altitude; đ?œ‘: solar azimuth; .

Fig. 1. A simplified drawing showing angle of obstruction

The number of hours the sun is shining each day that is the number of hours between sunrise and sunset each day. In latitudes above 67° the sun shines for 24 hours during part of the year. Surprisingly, when averaged over the year, the sun shines an average of 12 hours per day everywhere in the world. In the northern latitudes the average intensity is lower than at the southern latitudes.

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

Fig. 3. A simplified drawing showing angle of obstruction at different heights and its impact on opposite building

Fig. 2. A simplified drawing showing angle of obstruction and obstructed light

Describing the current situation:

Fig. 4. Analyses of sunlight incident on building facades according to showing angle of obstruction in such variables

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

đ??ť đ?œƒ = arctan [ ] đ?‘† 10

đ?œƒ = arctan [ 8 ] đ?œƒ =51.3Ëš In this case the angle of the obstacle is 51.3Ëšfor the ground floor it is still possible to achieve good daylighting, providing the obstruction is not continuous, and it is narrow enough to allow daylight around its sides.

Solar calculations based on location and date. According to literature above (Dr. Abdulsalam A. Alshboul and Dr. Hussain H. Alzoubi research about Low energy architecture and solar rights), A design table for cold season was prepared to help planners and architectural designers maximize solar energy utilization in buildings. It identifies the most appropriate setbacks that planners and designers should allow to maximize the insolation.

Table 3 Recommended setbacks to achieve the targeted Insolation percentages.

Table shows the best combination between the two main variables, setback (S), and building height (H), to reach the highest percentages of solar insolation on southern facades. They were categorized into four segments of percentages, 25%, 50%, 75%, and 100%, which represent total received insolation by building facades.

Following this table allows solar accessibility for all adjacent apartment blocks in the cold season. The relation between the setback (S) and the height (H) was estimated based on the solar altitude (b), solar azimuth (F), and the profile angle PA. The solar profile is necessary to determine the solar availability from left and right sides of apartment blocks.

The relationship between solar altitude, solar azimuth, and solar profile is given by the following equations: Tan PA= H/S S= H (cos ɸ)/tan (β) According to this design table a reference line is taken at 2m on the existing building.

This is the assumed position of the top of windows in the existing building. A 25 degree line is then drawn towards the proposed building. If the whole proposed development falls underneath the line drawn at 25 degrees, there is unlikely to be a detrimental effect to daylight on the existing property.

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

Fig. 5. A simplified drawing showing angle of obstruction

If the proposed building falls above the 25 degree line in any way, it is likely that further tests will be required to establish the exact impact the proposed development would have on daylight to the existing property. If the obstructing building is taller than the 25 degree line, it is still possible to achieve good daylighting, providing the obstruction is not continuous, and it is narrow enough to allow daylight around its sides.

Fig. 6. A simplified drawing showing angle of obstruction

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

Results and discussion Based on analytical study for residential zone and through studying the relationship between building height and setback to achieve the targeted angle of obstruction. The researcher found that current building regulations have to be modified to enhance natural light and ventilation for occupants.where Architect and planners have to design their buildings and city planning according to the climate characteristics. where regulations have to be modified according to sustainable planning not on land use planning.

Recommendations There is additional guidance to suggest suitable window design according to the obstruction of neighboring windows.

If the obstruction angle is: > Less than 25 – a conventional window design should give reasonable results > Between 25 and 45 – enlarged windows or changes to room layouts should be considered in order to provide adequate daylight > Between 45 and 65 – adequate daylight would not be provided unless very large windows are used > More than 65 – it is often impossible to provide reasonable daylight, even if the whole wall is glazed There are some simple ways a design can be improved when daylight is limited and internal layout restrictive. Window sizes should be increased to maximise natural light, it is more effective to do this by raising the window head height to allow more light to enter and the light to be distributed into the room. Reducing the depth of the plan is a very important way to improve the daylight quality in a building. Another method is to improve the external surface reflectances. Having light external paving will allow the light to be reflected back to the building. Internally light colours will allow for light entering the building to be reflected rather than absorbed.

Conclusions This research has a great significance on assessing current setbacks regulations.Where these regulations have to be modified according to the characteristics and specifications of the region climate and it recommend designers, planners and decision makers to rethink in city planning to enhance human comfort by providing natural light and natural ventilation, therefore Greater Amman Municipality (GAM) should reconsider building regulations according to climate change.

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Research course: Research methods by Dr. Abdulsalam A. Alshboul

References 1. Greater Amman Municipality. Book of building regulations. Amman, Jordan; (1979).

2. Boubekri, M., 2014. Daylighting Design: Planning Strategies and Best Practice Solutions. Birkhäuser, Basel, Boston.

3. Haans, A., 2014. The natural preference in people's appraisal of light. J. Environ. Psychol., 39: 51-61.

4. Boubekri, M., I.N. Cheung, K.J. Reid, C.H. Wang and P.C. Zee, 2014. Impact of windows and daylight exposure on overall health and sleep quality of office workers: A case-control pilot study. J. Clin. Sleep Med., 10(6): 603-611.

5. Abdulsalam A. Alshboul and Hussain H. Alzoubi research about Low energy architecture and solar rights, Renewable Energy 35 (2010) 338.

6. Ünver, R., Öztürk, L., Adigüzel, S., Çelik, Ö., (2003). Effect of the facade alternatives on the daylight illuminance in offices. Energy and building, 35: p. 737-746.

7. Hopkinson, R., Petherbridge, P., Longmore, J., (1966). Iluminação Natural, 776p.

8. Ng, E.; Wong, N., (2004). Better daylight and natural ventilation by design. In PLEA International Conference. Eindhoven, Netherlands, September 19-22 9. BEATLEY, T. 2010. Biophilic Cities: Integrating Nature Into Urban Design and Planning, Island Press.

[10] Sofia Behling, Stefan Behling. Sol power: the evolution of solar architecture Munich. New York: Prestel; 1996.

11. Abdulsalam A. Alshboul and Hussain H. Alzoubi research about Low energy architecture and solar rights, Renewable Energy 35 (2010) 333–342.

12. Dr.Khaled Al Omari and Arch.Hind Alshoubaki research about Effects of Setbacks on Solar Accessibility In Amman, Jordan, International Journal of Applied Engineering Research ISSN 0973-4562 Volume 10, Number 14 (2015) 34183.

13. U.S. Green Building Council, Inc. (USGBC) Reference guide for building design and construction, (2013) 597-602 14. Esra'a Alqudah, Hibatullah Stetieh and Rizeq Hammad research about Catching Daylight: Improving Natural Illumination Levels in Deep-Plan Drawing Studios at the University of Jordan, Research Journal of Applied Sciences,(2018) 220

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