Harvesting Daylight in Bahrain

Ahmed Al Sadoon, Architect at MSCEB

Daylight is a powerful resource
Daylight is the powerful resource we have plenty of in Bahrain. If properly utilized, it can reduce as much as one-third of total building energy costs. The architectural design of houses and flats can play a vital role in doing that.

For example, avoiding unwanted shading through careful design of the height of a building in comparison to nearby structures. In order to achieve maximum exposure, the orientation of the building must be studied, for instance maximizing the north and south-facing façade while minimizing the façade facing east and west to better control daylight admittance. Furthermore, long and narrow building forms better maximize daylight harvesting.
The sizes and placement of windows must be designed in a way that allows for enough daylight while avoiding the admittance of direct sun on task surfaces or into the occupants’ eye levels. For example, south windows should not be oversized to avoid glare and excessive heat gain, in contrast, north windows are to be utilized to bring in diffused light and require a glazing treatment for low heat loss. However, this shouldn’t be over done as oversized windows can cause excessive heat gain and thus require higher cooling load in summer and increased heat loss in winter.
When designing windows and skylights, it is essential to select the correct window glazing. Factors to be considered include the solar heat gain coefficient, the U-value to avoid heat loss and light transmission for good visibility. Besides ensuring that the thermal break of the window frame construction is effective.
To increase the daylight level in the depth of the living space, interior surfaces of high reflectance are preferable, such as using light muted colours for ceilings and surfaces next to windows for indirect lighting, and avoiding dark surfaces, especially for back walls. To better avoid glare, it is ideal to locate the reflector system above the eye-level.
In summer, buildings with large glazing areas can lead to increased heat, which in turn can result in higher energy consumption for cooling; this necessitates the use of shading devices to achieve thermal comfort. Trees can be a natural solution, alternatively the use of technical elements such as insulation, louvers, fences, shutters can also be effective.

Hala Nehad Abusharaq, Architect

Energy-efficient glazing systems

Thermally efficient windows and doors not only help reduce energy use, they provide value by reducing heating and cooling costs. The energy-efficient glazing systems used by Marvin are state-of-the-art.

Skylights offer excellent daylighting and have the potential to displace much electric lighting, thus saving on lighting and, potentially, cooling energy. 

Skylights are widely viewed as a desirable feature for buildings that have human occupation during at least daylight hours.
Shades can keep the heat and glare of direct sun from coming through windows. They can also keep direct sunlight off of walls or roofs, to reduce cooling loads.
Energy efficient windows make your home more comfortable, dramatically reduce your energy costs and help to create a brighter, cleaner and healthier environment.
The SHGC is the fraction of incident solar radiation admitted through a window, directly transmitted as well as absorbed and subsequently released inward.

Dr Ghaleb Khadem, Bahrain Architect and Interior Designer

It’s really not the case of quantity but quality

Within Bahrain improving the accessibility of daylight to reduce electrical consumption could be done basically by allowing more sunrays into the rooms; however it’s really not the case of quantity but quality.
Bahrain is a sunny island located in a hot region and therefore the risk of raising the indoor temperature by increasing the sun light amount coming into the room is high. If the comfortable zone aspects were not considered the rising temperature would waste way too much more electrical power over cooling system than what would be saved by reducing power consumed by artificial light.
Hence, the first consideration must be the function of the room itself; a study room or home office would need different light amount than bedroom; therefore the size of the windows and the location of the room should be decided upon. For example, bedrooms should be located on the north while the study room should be in the south.
The height of the window could be considered as well because light coming from the part of the window which is from the ground to one-and-half metre height is nearly useless functionally while the part from above one-and-half metre to three metres is the most valuable functionally.
Now consider the location of the window in the room; if we take a bedroom as an example, locating the window over the bed would be rather disturbing than functional; while locating the window over the dressing would help reducing the light needed while selecting cloths.
Finally, the materials play a major role in allowing the needed light without raising the room temperature noticeably; however the material should, at the same time, maintain the quality of light tone because some materials do shade some colours of the light which could disturb the eye and reduce the visibility.

Ebtihal Salem, Bahraini Freelance Interior Designer

Natural lighting through architecture solutions

Simply using more natural lighting through architecture solutions is the main way to save electricity. Here are some tips to take advantage from the natural daylight: Building orientation plays an important role as the sun rises in the east and sets in the west, the side of the building that is utilized for solar gain needs to be facing the south to take maximum advantage of the natural day light. If the building’s axis is located on the east-west direction with its longest dimension facing the south, more of the building is situated to absorb the natural daylight.
The second point is dividing the building interior area for two zones , activity zone which needs more lighting and less-activity zone which needs less lighting. Then put activity rooms such as living room or children playing room on the south to take maximum advantage of the sun light.
Use large scale windows with light colour curtains and blinds as window covering. Consider window position according to the room and the wall. For example using vertical window in ground floor area can take more advantage from the natural day light.
Skylights are a simple way of introducing light to rooms right below roof level. Skylights over stairways, for example, can bring light into the centre of a house.
Place a mirror on a wall adjacent to a window or opposite a window. When placed adjacent a mirror will mimic the window and make it seem like you have more windows in the wall. When placed opposite, the mirror will reflect light and views from the window.
Reflective surfaces like a back-painted glass backsplash can bounce light around and give the impression of more light when windows are limited.
Ceilings a little lighter than walls is a good choice for reflecting light. Flat white is best if your walls are white, but if you have dark walls, be sure to go with a slightly lighter colour on the ceiling. As my last point, also using Light Emitting Diode (LED) and Compact Fluorescent Lights (CFL) bulbs have revolutionized energy-efficient lighting.

Balqees Akram Mohd, Interior Design Engineering  Student at Gulf University, Bahrain 

Simple steps for daylight penetration

Maximum daylight penetration could be achieved with the combination of intelligent urban planning, architect and interior design. If these three parts are done smartly , then we get quality light without allowing heat in interior space.
As an interior designer I believe colours, materials and furniture orientation have to do a lot with day light. We can see nowadays people often use dark coloured walls or wallpaper knowing our climatic conditions which is hot and humid mostly; we should avoid using dark walls as these colours demand more artificial light; therefore we shall switch to light colour.
Secondly materials have also a great impact on daylight; it should be wisely decided what materials we use in interior space; shiny tiles for flooring is good choice as it will reflect the daylight which would fall from windows. One of the best materials to use within walls is glass bricks; it will provide daylight in different colours without any heat gain in interior space and because it has a void which provide insulation itself. Use of mosaic structure is also one of the best techniques to allow daylight and reduce heat. Mosaic structures are very prominent in Bahrain’s vernacular housing. Wrong furniture orientation can also reduce daylight within interior space; inadvertently blocking windows when arranging your furniture can cut into a room’s natural light. Rearrange your space to keep natural light sources free and unobstructed. Keep larger pieces toward the center of the room. Even knick-knacks on a windowsill block a surprising amount of light. For best results, don’t forget to maintain your outdoor spaces. Trim hedges or branches away from the windows. Also, carefully consider the placement of porch swings and other patio furniture. These steps will increase natural light inside your home.

Ashutosh Jha, Senior Architect at MEBEC

Energy conservation should be top agenda

Energy conservation or optimization in any building should be the top of the agenda for any designer. One design approach should be dealing with daylight.
Use of efficient daylight in the gulf region makes perfect sense; this region is blessed with plenty of sunlight throughout the year.
Passive design strategy right at the concept stage makes all the difference in order to integrate daylight in most occupied areas of any building.
Integration of daylight can happen in two stages... the first to minimize the solar heat gain and second to consume glare free natural light inside the building.
Site planning, orientation of the building and massing early in design stage matters. (Minimize Solar Heat Gain)
1. Correct orientation of any building helps in minimizing solar heat gains and building remains thermally comfortable for occupants.
2. Certain orientation provides more exposure to the sun, understanding the sunpath and their behavior in different parts of the year is key for any designer.
3. The massing of a project can provide shade and reduce the solar heat gain.

While we minimize the solar heat gain, it’s also important to have adequate daylight in order to reduce the artificial day lighting during the day time.
1. Bringing the daylight through window openings at appropriate heights is key and it’s important that these should be integrated with overall image and aesthetics of the building.
2. If a designer is aware that what depth of floor plate will work from daylight perspective, it helps a great deal, especially in office and residential buildings.
3. Design elements and techniques like overhang, light wells, light shelves, reflective blinds etc. are key to integrate the daylight into the building.

Ibtesam Muhammad Ziyad Alhoutary,Lecturer at Interior Design Engineering, Gulf University Bahrain 

Need for natural ventilation 

Natural ventilation is the process of supplying air to and removing air from an indoor space without using mechanical systems. It refers to the flow of external air to an indoor space as a result of pressure differences arising from natural forces. There are two types of natural ventilation occurring in buildings: wind driven ventilation and buoyancy-driven ventilation. Wind driven ventilation arises from the different pressures created by wind around a building or structure, and openings being formed on the perimeter which then permit flow through the building. Buoyancy-driven ventilation occurs as a result of the directional buoyancy force that results from temperature differences between the interior and exterior. Since the internal heat gains which create temperature differences between the interior and exterior are created by natural processes including the heat from people, and wind effects are variable, naturally ventilated buildings are sometimes called “breathing buildings”.
Design guidelines are offered in building regulations and other related literature and include a variety of recommendations on many specific areas such as:
l Building location and orientation
l Building form and dimensions
l Indoor partitions and layout
l Window typologies, operation, location, and shapes
l Other aperture types (doors, chimneys)
l Construction methods and detailing (infiltration)
l External elements (walls, screens)
l Urban planning conditions
l Maximize wind-induced ventilation by siting the ridge of a building perpendicular to the summer winds
l Widths of naturally ventilated zone should be narrow (max 13.7 m [45 feet])
l Each room should have two separate supplies and exhaust openings.
• Window openings should be operable by the occupants
• Consider the use of clerestories or vented skylights.