Part L final draft details released

The long-awaited changes to the Building Regulations covering conservation of fuel and power were published in September and will take effect from April next year.

Four Approved Documents which set out the requirements of the regulations in detail, covering new and existing domestic and non-domestic buildings, were published in final draft form. The Office of the Deputy Prime Minister said that the new regulations would save a million tonnes of carbon annually by 2010, equivalent to the emissions from more than a million semi-detached homes.

Initial reaction was that the only major surprise was the ‘disappointing’ target for improvement for domestic dwellings, said Graham Raven, Steel Construction Institute General Manager for Construction Technology. The target, compared with a building meeting the 2002 regulations, has been set at 20% for gas-heated dwellings, reduced from an expected 22% and the initially-proposed 25%.

For non-domestic buildings the target depends on a number of factors but in broad terms a 23% improvement for naturally-ventilated buildings and 28% for mechanically ventilated or air-conditioned buildings will be required.

The new regulations will introduce mandatory testing of airtightness for buildings above a certain floor area, while the use of ‘low or zero carbon technologies’ such as solar panels, heat pumps and wood pellet stoves will contribute towards the required improvement in energy efficiency.

A ‘whole building’ approach to calculating thermal performance will be introduced. Both methods for achieving this — SAP 2005 for domestic dwellings, and a beta version of the software-based Single Building Energy Model for non-domestic dwellings — were expected to be published by the end of September. Click here to see feature.

The SCI has been appointed assessor for steel-framed house designs, following the recent publication of a chapter covering steel-framed dwellings as part of the National House Building Council’s standards. This parallels the arrangements for timber-framed housing and by removing the need for third-party certification makes it easier for house builders to adopt steel frame. Once the supplier’s system manual has been assessed by the SCI, site inspections only have to ensure the manual has been followed. Metek has become the first company to seek approval under the scheme.