GAPP Architects has designed an intelligent facade concept applied to three major commercial developments in Kenya and Botswana.
Three major office developments currently under construction in Kenya and Botswana will each soon boast an intelligent ‘brise-soleil’ facade designed by GAPP architects / urban designers (GAPP), specifically to make the most of the African sunlight without the drawback of heat gain.
The facades involve either a glazed envelope or cavity wall, together with a secondary veil designed to block direct sun, but at the same time let diffused or reflected light into the building, according to Simon Bird, senior associate at GAPP.
“Therefore one still gets the maximum benefit of natural light, which helps to reduce internal lighting costs, while the building cooling costs are reduced since the facade prevents heat gain to a great extent during periods of intense solar exposure,” he states.
Britam Tower, Nairobi, Kenya
A 30-storey tower office block of about 30 000m², Britam Tower, is envisioned as an iconic prism-shaped, high-rise development in the city centre of Nairobi.
The building’s full-height glazed curtain wall facade will be screened by a veil made out of hollow ceramic rods that are horizontally laid. These 1,5m long, 50mm x 50mm rods are spaced varyingly across the high-rise, depending on orientation, to effectively reflect light into the building without the heat.
Mashiara Park, Nairobi, Kenya
Another office development in Kenya, Mashiara Park, will display a facade based on the same principle but interpreted differently in terms of the exterior details.
Instead of ceramic rods, metal louvres will be applied as a sun filter. On the northern and southern facades, overhangs and sun shadings will provide sun protection, while the eastern and western louvres will receive perforated, electrically operated vertical fins which can be closed completely, blocking out the sun while letting through filtered light.
BURS Head Office, Gaborone, Botswana
The new headquarters of the Botswana Unified Revenue Service (BURS) is a square block of four buildings built around a landscaped courtyard, which mimics and use the ecological closed-cycle principles of the Okavango Delta.
The facade for the BURS building will also comprise 1,8m long, 50mm x 50mm rods on its outer skin such as Britam Tower, but in this instance the rods will be laid vertically with deeper protective overhangs to deal with heat gain on the northern facade. Another variance on the concept is that instead of the glazed curtain walling, the BURS building features a brick cavity wall with punctuations of windows to improve the building’s thermal capacity and reduce cost.
In addition, to counter noise from a railway line that runs past the development, a special type of acoustic build-up will be added to the facade. Some parts of the facade will comprise two layers of glazing with a 200mm cavity in-between.
Applying the same principle, with slight variations, each facade will intelligently manage natural daylight, heat gain and acoustics.
GAPP architects / urban designers
Tel: 011 482 1648
Intelligent facades benefits:
– Sun protection.
– Heat gain.