The rules are likely to cost developers an additional £3000 per home, although it is understood that this will be partly offset by a reduction in stamp duty levied on the purchaser. They will be enforced by local authorities as part of the planning process.
The tough carbon emission targets, 25% above that currently required by Part L of the Building Regulations, are set to be recommended by the government's Sustainable Buildings Task Group. The group is also to recommend that PFI schemes be built to improved energy efficiency standards.
The outline recommendations, which have been leaked to Building, also include setting mandatory pressure testing to measure new buildings' airtightness.
The energy proposals have been attacked by the House Builders Federation. Pierre Williams, the HBF's communications director, said the costs of mandatory energy improvements would hold up building in the Thames Gateway.
If you pile on the costs you reduce the viability of development
Pierre Williams, HBF
He said: "They will come up with a nirvana-like solution that is totally impractical in the real world. If you keep piling on the costs you will reduce the viability of development particularly on brownfield, which is only marginally viable anyway."
The task group was set up by the government at the Better Buildings Summit last October to look at how the government and the construction industry could improve the quality and sustainability of new and refurbished buildings.
The group's recommendations may be included in the government's next energy white paper. The task group will submit its final recommendations to the government later this month.
In October, deputy prime minister John Prescott said: "The task group will play a key role in identifying the improvements needed to create truly sustainable communities." Its proposals are expected to emerge in changes to the Building Regulations in 2010 and beyond.
The group has focused on energy and water savings, waste reduction, and the sustainable use of timber and other construction materials.