Energy Saving Glass
SGG Planitherm®, Clearly the Way Forward
The consultation period for amendments to Building Regulations part L is now closed, so what are the likely outcomes for future legislation? The BFRC Window Energy Rating system is now unlikely to be included in its proposed form and average whole window U-values may yet be lowered to 1.8 W/m2 K for the window replacement market.
Certainly at present, high performance low-E products like SGG Planitherm® Total and SGG Planitherm® Futur N from Saint-Gobain Glass enable a wider range of frame types to comply with current regulations, affording greater flexibility for designs and specifications to architects and fabricators. In the not so distant future, the superior thermal insulation performance of these products will be the minimum requirement for most applications.
The consultation document as a whole clearly demonstrates the government’s commitment to the European ‘Energy Performance in Buildings Directive’ (EPBD) which calls for member states to adopt tighter thermal regulations, taking into account both heating and cooling energy savings.
‘As such, the suggested replacement window U-values may well still be lowered to 1.8W/m2k, bringing English and Welsh regulations in line with Scotland. Certainly the feedback we received during the consultation process suggests that many companies called for such a move. Even if regulations are not tightened this time around, section 6 of the consultation document confirms the intention to raise U-value standards for glazing in 2007, just one year later.’ says Saint-Gobain Glass.
As far as the proposed BFRC Window Energy Rating system is concerned, Saint-Gobain Glass discovered a number of fundamental flaws in the calculations and methodology presented. These findings have been passed on to the ODPM, and a full technical audit has been requested. It is now unlikely to be included in the final version of amended part L.
For new build, where the total energy performance of the whole building is now considered, average window U-values are less relevant. It is clear from all the working examples given in the consultation document that higher performance windows of at least 1.8W/m2k would be encouraged under such a system, as this is a relatively cost effective and practical option for designers.
Longer term, section 6 of the consultation document clearly demonstrates the government’s intention to further raise U-value standards for glazing in 2010. The table of aspirational indicative U-values introduces average standards for windows doors and roof-lights of as low as 1.4 W/m2K.
‘The SGG Planitherm® range is unsurprisingly Europe’s best selling Low-E glass and the UK’s leading soft coat brand, offering enhanced thermal insulation, a remarkably neutral appearance and exceptional clarity. SGG Planitherm® easily fulfils the ever increasing requirements of the customer and that of legislation, representing the clear way forward for the glass and glazing industry.’ says the company.
RED DEAL WINDOWS USE PLANNITHERM IN OUR A/B RATED UPVC WINDOWS
