Higher performance, hard coat low E glass appeared to be the answer to Document L, so virtually any window would achieve the required 2.0 U value in England and Wales, and 1.8 in Scotland. But the results of a comprehensive test programme presented by the GGF at Glassex 2004 may cast doubt on this, says Edgetech.

Various configurations of PVC-U windows with hard coat low-E and aluminium spacer bars struggled to get below the required 2.0 U value. Warm edge spacer bars, and Edgetech's Super Spacer in particular, boosted performance by an extra 0.2 U value enabling all the windows tested to pass the standard with ease.

Given that hard coat low-E glass and aluminium spacer bars currently represent the bulk of sealed units installed in the UK this is worrying. If warm edge were not available now as a get-out-of-jail card it would be even more of a concern considering the Government's plan to demand even better energy performance from our windows in changes to Building Regulations.

It is often said that if you want to know what we will be using in the UK in the next few years look at trends in the USA. Currently 90% of sealed units in North America benefit from warm edge technology says Edgetech, and it's starting to grow fast in the UK.

Those who keep up with developments in sealed unit technology will know Gerhard Reichert, Vice President of Business Development at Edgetech IG Inc., a noted expert on the subject. It is greatly down to Gerhard's technical expertise and passion for Edgetech's Super Spacer technology that the US swung so comprehensively behind warm edge spacer bars.

Where and when did warm edge technology develop? How and why did it happen? What are the technical developments that made it possible? How will we cope with further changes in Building Regulations and much lower and demanding U values?

The answers are in the latest paper from Gerhard Reichert, available free of charge from Edgetech on 02476 705570.

Source

Glass Age