How glass manufacturers are helping deliver sustainability
How are glass manufacturers responding to the growing demands for sustainable buildings and what can they expect from 2010? ConstructionWeekOnline speaks to industry experts to find out.
Glass is one of the most popular choices of cladding system used by architects across the GCC. You only have to drive down Dubai’s Sheikh Zayed Road or glance at the skyscrapers of Saudi Arabia to notice that.
But, while it is visually pleasing, glass remains the greatest contributor to heat build up inside a building.
“The heat doesn’t come through the wall, the roof or the floor; it comes through the window, so glass is critical,” says Emirates Glass technical consultant Arthur Millwood.
So why do so many architects choose this material as their choice of cladding system? According to Millwood, it all comes down to visual amenity.
“We all like daylight,” he explains. “And, the fact of the matter is that, even today, the combination of aluminium and glass is still a very cost effective way to cover a building.”
There is a growing need to design buildings according to green building standards and with the forth-coming revision of Dubai Municipality’s (DM) Code of Practice for the use of Glass for Windows, as well as the Emirates Green Building Council’s imminent green building guidelines for the UAE, 2010 can expect even stricter principles.
The DM is expected to adopt Solar Heat Gain Coefficient (SHGC) as the prime indicator of the solar-resistance of window-glass. SHGC is the actual percentage of the amount of solar energy transmitted through and reflected off a piece of glass.
“Shading Coefficient is now becoming out-dated, since SHGC (an American concept) is being adopted worldwide as a more meaningful indicator of glass-performance when exposed to the sun,” says Millwood.
So is it green versus a glamorous, cost-effective system or can we have the best of both worlds? Swiss Middle East, which handles the design of building envelopes, agrees with the latter.
“We should maybe reduce the use of glass [in a building’s outer layer] to 30% or 40%,” says Swiss general manager Mohammed Enany. “We like to use glass but not a huge amount.”
But, Millwood argues that glass doesn’t have to have a negative impact on the environment: “It is not a question of too much glass in buildings, rather, it is a question of too much of the wrong glass and we hope that this new awareness of glass-performance in our severe desert environment will lead to a more informed and more efficient use of glass,” he says.
“The sun will shine tomorrow and the problem will not go away. We have to minimise heat-gain into our buildings by recognising that windows are the conduit for this heat and therefore, the main solution will lie in reflective high-performance glass.”
Emirates Glass’s new multi-million dollar facility is soon set to come online in Dubai Investment Park and will produce a new range of glass, which can be coated with solar applications before the tempering process (a heat treatment technique to harden the glass).
“This is a major technical advance for our company as we will now be able to supply full stock sheets of annealed (not yet heat-treated) glass to other glass processors who will perform all the subsequent down-stream activities to reach the finished product as installed on the building,” explains Millwood.
“The big benefit is that the processor can order the raw material stock sheets from Emirates Glass, well before the availability of the final cutting-lists. By having the raw material already on-hand, they will overcome the problem of longer lead-times associated with “traditional” pre-tempered coated glass.”
And, when it comes to glass, Cladtech International is also following the green trend. “We support our client in the design stage by providing them the proper solution for the materials to be used to decrease the energy consumption,” says Cladtech president Henrik Christiansen.
“There are a lot of factors that might affect such a decision, starting from the conceptual design stage, going through the glass types and thicknesses, as well as the coatings, which will reduce the amount of heat transferability between the outer and inner sides of the building.”
Al Abbar Architectural Glass (AAG) also have green expectations for 2010: “I hope that all concerned parties will finally implement their green promises and start understanding the worth of the local industry with regards to manufacturing and processing the goods locally,” says AAG director for the product and technical department Jean Lelievre.
AAG is introducing three new gold-reflective glass-types this year including CoolRay Gold, CoolRay Amber and CoolRay Topaz.
Gold’s high reflectivity and hence ability to reflect heat, has led to the increasing use of glass coated with a thin film of gold in modern buildings.
But, while green technologies are rolling out, the financial crisis is still lurking around every block. And, with the huge drop in building material prices and cancelled projects, glass specialists in the Middle East are feeling the strain.
Many firms bought their materials when prices were at their peak and, now they have dropped, cladding companies have been forced to lower their rates.
“Towards the end of 2009, conditions deteriorated substantially mainly due to lack of collectable money in the market. This situation still shows no sign of recognisable improvement,” says Millwood.
Business is expected to suffer the most in Dubai due to the amount of projects on hold there. “Consider that our materials come on site towards the finishing stage of the building and you will understand that 2010 will be a year of survival,” adds Millwood.
However, there are regional markets that are improving and can expect heavy investment from construction companies this year.
Emirates Glass is now taking advantage of active construction projects going on in Saudi Arabia, for example. “The new Dubai is Saudi Arabia,” Millwood says.
“Emirates Glass, together with our sister company in Riyadh, Saudi American Glass has been much more closely integrated into our Middle East operations. We have consolidated our efforts and we are operating now under one sales team.”
When considering the choice of glass coating and the use of glass in general there are local regulations that must be reviewed, including those aimed at minimising solar thermal heat gains. Further regulations are expected to be introduced in the future as the region strives for high levels of sustainable building.
Glass companies to know
Emirates Glass is based in Dubai’s Al Quoz Industrial area, with its new coating lines located in Dubai Investment Park. Most recently, the company provided cladding for all buildings associated with the Formula 1 racetrack at Yas Island, Abu Dhabi.
Al Abbar Architectural Glass
Al Abbar Architectural Glass (AAG) was established in 1959 and is an autonomous glass processing company that provides assistance in the technical and commercial needs of glass-related topics. The firm’s services include practical advice on the correct selection of glass, substrate and coating for a project with regards to the aesthetics and required solar and thermal performance.
Established in 2006, Cladtech is a fairly new company to the Middle East but has secured projects such as the Elite Residence Tower at the Dubai Marina and is supplying cladding to the new Dubai Metro stations. In Saudi Arabia, the company has set up a sales office and will now be working on the Jawharat Alfalak tower in Jeddah.
Reem Emirates Glass
Reem Emirates Glass is one of the largest glass processors in Abu Dhabi UAE, located at industrial city of Abu Dhabi. It is committed to provide solutions for all kinds of glass processing. The company’s product range includes heat treated glass insulated units and laminated glass.