Controversy over 30% glass limit on buildings
Regulation coming into effect next year divides industry opinion.
New rules set to restrict the amount of glass on a building’s facade have sparked controversy among construction industry professionals.
The regulations, which will give designers the option of limiting glass to 30 percent or showing that they can keep solar gain to the level of the 30 percent design, have attracted a range of opinions from within the sector.
Applying only to the Emirate of Abu Dhabi, the rules will therefore give designers the option of a prescriptive or performance-based approach to achieving energy savings.
Talking about the DMA’s plans, Abu Dhabi-based architects Stride Treglown’s general manager Nathan Hones said: “The introduction of regulations to limit the amount of heat gain and therefore energy required to cool a building is absolutely the right way to go, as this is the single most important factor in reducing our carbon footprint and decreasing an already strained energy resource bank.
“However, we must be careful not to stifle the designer’s creativity with prescriptive controls. Mandating that a building has only 30% windows basically states that there is no other way to address heat gain.”
BDP architect’s environment design associate Steve Merridew, was more than confident that the prescriptive approach was the best way forward.
“The introduction on maximum glazing percentages under Estidama is a positive step towards the delivery of more environmentally-conscious architecture in Abu Dhabi,” he said.
“While glazing is a very valuable element of the materials palette for facilitating daylight ingress and connectivity with the outside, its poor insulation and solar control properties mean over specification leads to energy hungry buildings in the region.
“This new guidance should ensure glass is specified more carefully and for maximum benefit, rather than as the default cladding option of the architectural zeitgeist.”
Somewhere in the middle, Inhabit Group’s senior associate Nicholas Lander says that the regulations certainly will force architects to be more creative, but that they have the advantage of not banning glass buildings altogether.
“I think 30% will be ok and is much more suitable to this region. Architecturally, it will force people to be more creative, but there is still the performance-based approach where you can have more glass if you can demonstrate the same energy saving, so there is still scope to have glass towers.
“Designers just need to put a bit more thought into it now.”
In an earlier interview with Construction Week, Zahid Mahmood, general manager of Material Lab UAE, a tester of construction materials and subsidiary of the SS Lootah Group, commented that glass façade was possibly the most important way of achieving energy efficiency in construction.
“While most people believe that technologies like insulating concrete forms and aerated concrete may increase due to the energy savings attributes, the reality is that buildings are more exposed to environment in terms of glass cladding.
“Therefore the use of proper glass with low ‘U values’ and solar heat gain, will be more effective in saving energy. The authorities should definitely be stricter on the use of glass.”
The regulations, which will come into force early next year, are part of a wider attempt by the Department of Municipal Affairs to encourage more energy efficient buildings in the Emirate.
They will come under the DMA’s Energy Code, which currently complements the Estidama Pearl Rating System put in place by the Urban Planning Council in April this year.