As the government plans to rein in energy emissions from buildings, a leaked document gives manufacturers and contractors an idea of just how stringent the Part L regulations are about to become
When it comes to Building Regulations there’s been little respite for builders in recent years. No sooner have tricky new acoustic regulations been implemented than a major revision of the energy regulation Part L looms on the horizon.

It has only been a year since the government imposed tough new energy standards but already it is looking at radical ways of forcing contractors and manufacturers to be even more energy efficient. A leaked draft document entitled Possible Future Performance Standards for Part L shows how determined the government is to cut the amount of carbon emissions generated by buildings.

The proposals hint at substantial improvements in the thermal performance standards of roofs, external walls, floors and doors and windows. Tables in the document suggest that the U value for external walls could improve from 0.35 to between 0.25 and 0.15 W/m2 K.

The government is also considering introducing pressure testing on new homes to ensure they are airtight. It may do so if it finds that poor workmanship is making new homes leaky and prone to heat loss.

The document is far ranging and considers every aspect of energy efficiency. For example, it asks whether energy used by domestic appliances should come within the remit of Part L. It is also looking at imposing performance standards on domestic air-conditioning units, which are increasingly appearing in a domestic settings.

The leaked document also reveals that the government is considering making swimming pools and small conservatories subject to Part L performance targets. On the retail and leisure side the document says that window displays may also no longer be exempt from U-value standards.

In buildings other than dwellings the document says that improved standards for air-conditioning and mechanical ventilation are vital and adds that humidity control devices should be regulated as they can result in significant energy consumption.

Existing stock presents a monumental challenge to a government intent on cutting carbon emissions by 60% by 2050. There are approximately 1.9 million businesses in England and Wales and 25 million households: every new building could be energy-neutral but if existing buildings are not improved then the government will struggle to meet its targets.

The government says it will look at making more refurbishment projects subject to Part L but it knows that if the targets are too stringent there is a risk that people will be dissuaded from making any improvements at all.

Amendments to Part L will come into force in 2005. Next year the government will publish the consultation document, when manufacturers and builders will know exactly what challenges they will face.