THE GOVERNMENT will unveil its efficiency calculations for the environmental performance of buildings in the spring.
A ministerial statement on essential energy efficiency performance levels for residential and non-residential buildings is expected in March.
This will help house builders and designers develop documentation and design computer tools aimed at evaluating the energy efficiency of the final building and its likelihood of conforming to the new Part L of the building regulations.
But any such design tools would need at least six months to fully bed in, claimed John Tebbit, industry affairs director at the Construction Products Association.
He said: 'The statement would give the industry an idea of what it should be aiming at, then we can start working out the supporting documentation. But it is vital that these tools are spot on from the start.'
Mr Tebbit said that working out the efficiency for non-domestic buildings and what products could be used to reach the efficiency targets would prove to be the biggest problem.
He said: 'On the domestic side the calculations will be similar to the existing Standard Assessment Procedure for Energy Rating of Dwellings but big issues will be on the non-domestic side and proving the useability of any calculation software.'
The new Part L is likely to be laid before Parliament at the end of July and fully introduced in January 2006.