Environment experts accuse the ODPM of dropping some changes to Part L for reasons of political expediency

The government has been accused by environmental experts of abandoning changes to the Building Regulations that would dramatically cut carbon emissions.

The criticisms, which come after the housing and planning minister Yvette Cooper announced the amendments to the Part L regulations this month, are aimed at omissions in the rules for dwellings.

Andrew Warren, director of the Association of the Conservation of Energy, said the Part L draft consultation included measures to force homeowners to improve energy efficiency when altering their homes. However, these were omitted in the amended version, which will come into force in April.

Warren said: “They got a positive response during the consultation but there has been a cop-out.”

He added: “In 2003 [at the launch of the energy white paper] Tony Blair said he wanted a step-change in how energy was used in new buildings. What we got was a small shuffle forward.”

In 2003 Blair announced that revised regulations would lead to a 25% improvement in energy performance of buildings. However, when Cooper announced the changes, she said the average figure for housing would be 20%.

Paul King, director of the World Wildlife Fund’s One Million Sustainable Homes campaign, said the government had backtracked over forcing homeowners to improve energy performance for political reasons.

He said: “It’s disappointing. I don’t understand why they would miss this opportunity so soon after winning the election.”

A proposal to include conservatories under 30 m2 within Part L was also omitted from the amendments. This was criticised by David Strong, managing director of BRE Environment (see below), who said it would mean the use of heating and air-conditioning would continue to increase.

Another concern was the announcement that airtightness tests in homes might not be mandatory.

Instead, housebuilders may be allowed to self regulate by complying with schemes similar to robust standard details, now used for sound testing under Part E. King said: “There isn’t a sufficiently strong case for self-regulation.”

Dave Baker, managing director of Robust Standard Details Ltd, said he was in favour of the introduction of a robust standard detail scheme.

He said: “It is a chink of light. There is a lot of work to be done but there are similarities between possible details for L and the robust standards details scheme for Part E.”