Death-knell for double glazing in Blair's green push
The government this week signalled the demise of standard double glazing as it rushed through new energy efficiency standards for buildings.
The revision of the Part L building regulations, aimed at cutting carbon emissions, came in parallel with Tony Blair's announcement of a £100 million investment in renewable energy and renewed commitment to cutting carbon emissions by 12.5 per cent by 2010, in line with the international Kyoto agreement.
In the House of Commons on Monday, construction minister Nick Raynsford unveiled the core details of the new Part L, which demands dramatic cuts in the amount of energy lost through windows, walls and roofs. Under the new policy, today's acceptable U-value for windows of around 3.3W/m 2K must be cut to 2.0W/m 2K. Environmental engineer Max Fordham described the change as 'a significant move' and said that more expensive low-emissivity glazing or triple glazing must now be used on new buildings. A typical 8m cubed house with eight windows would cost an extra £250 to glaze, he said.
The new regulations also crack down on wall insulation, cutting the U-value for walls from 4.5W/m 2K to 3.5W/m 2K. However, this is less stringent than the original proposal of 3.0W/m 2Kand experts say this is unlikely to lead to a revolution in construction methods. 'At 3.0W/m 2K, the housebuilders said they would switch to timber or steel framing systems, but at 3.5W/m 2K they will not, ' said Design for Homes director David Birkbeck. 'This will not mean the end to cavity brick and block construction.'
The designer of the low energy BedZed housing development in London, Bill Dunster, described the measures as 'pissing in the wind'. He said they will result in housebuilders using 300mm insulation instead of 100mm and making windows smaller to create 'depressing airtight buildings'.
'This is so far short of the mark that it isn't very helpful, ' he said. 'Given the global warming issue we need to take very extreme measures.'
Housing alone accounts for 35 per cent of all carbon emissions in the UK.
'These building regulations are tied into the Kyoto commitments but they have been very strongly trimmed by the pressure groups - architects and builders, ' Fordham said.
The decision to release details of Part L before the linked Part E regulations on sound insulation also illustrates growing government concern that the UK is not on track to hit its Kyoto targets. In January, think tank Cambridge Econometrics released figures showing that the UK is heading for a 6.5 per cent reduction. Sources close to the government said that the findings had panicked it into pushing through the new regulations.