Features Business intelligence Contracting
European Scene: August 2011

It is happening everywhere: governments are setting targets to reduce carbon and save energy.

It is happening everywhere: governments are setting targets to reduce carbon and save energy. The feeling here is that the targets are stringent, but I guess I can’t complain because the U.K. started setting goals from a long way behind the rest of the world.

Britain has the draughtiest, leakiest (in energy terms) buildings in Europe. For decades, nobody cared. Sometimes elderly people would die of hypothermia – inside their houses – but tucked up as we are behind the Gulf Stream we have never had seriously cold winters, so we didn’t bother much with girly stuff like double glazing and insulation. I am old enough to remember getting up in the morning and seeing ice on the inside of my bedroom window.

The situation has been changing since the mid–1980s, when we started to see double-glazed windows and central heating become the norm, but the government is determined to do better. Last year, new building regulations specified stringent U-values for windows. At the time there were a lot of politics surrounding this as various organizations vied with each other to approve and certify compliance. Nine months on, they have all driven a coach and horses through the original specification and established new, quick, easy and, more importantly, cheap ways for window manufacturers to comply with the requirements. The target is to reduce energy consumption compared to 1990 by 34 per cent by 2020, heading for 80 per cent by 2050. As far as windows are concerned, U-values are due to fall again quite substantially by 2013.

To drive matters along, the government has come up with The Green Deal. Basically this will mean that, having assessed a property, an energy supplier will be able to sell energy-saving products to the householder, the cost being added to the energy bill and paid-for overtime.

There is a general consensus in the industry that the only way we will be able to meet future energy levels will be to move to triple glazing. Considering that until the mid-’80s and well into the ’90s the majority of glazing was single-pane glass, mostly in poor-quality timber frames, we have only just got to the point where double glazing is the norm. Now the whole thing has to be redesigned.

The more stringent requirements may make some existing materials unsuitable for window frame manufacture, and even some styles untenable. Vertical sliding windows are not unusual in the U.K., especially in older properties. Even with double-glazed sealed units and vinyl frames, it is notoriously difficult to achieve low U-values for vertical sliding windows. Some think aluminium will struggle to meet the requirements. Though its use in the domestic market is very low, it is the frame material of choice for commercial buildings. When you factor in sustainability, even timber has its problems. The best these days is engineered timber; softwood has a high maintenance requirement and a relatively short useful life, especially if it is not maintained. Hardwood is really a no-no, especially from rainforest sources, and requires good provenance if it is to be legal.

Triple glazing is generally regarded as a positive thing. The industry is facing some pretty serious consolidation. Recently Bowater Building Products, a company that had already swallowed one old established window system company, was itself taken over by Veka. We badly need to find a new angle. In this respect, triple glazing is a gift. It means more glass, more spacer bar and edge sealant (warm-edge of course), stronger frames (therefore, more compound) and stronger hardware, all making for more expensive windows.

Pilkington does have a wafer-thin, vacuum-sealed unit that was developed by its parent, Nippon Sheet Glass. Its U-value is so low it could do the job in existing frames and save all the hassle. At the moment, it is very expensive and has only been used in the U.K. on a few so-called heritage jobs (see my last column). But then, given the opportunity to sell a third more float glass, who is going to mass-produce a product like that?

John Roper is the editor for The Installer, The Fabricator, The
Conservatory Installer and Glass Works magazine published in the U.K.