Construction Products Association president John Colley called on the government to provide householders with incentives to achieve targets.
 
Colley, speaking at the association's annual lunch, said: "If we are talking about reducing carbon emissions, then the first place to start must be the existing housing stock.
 
"The average house in this country emits four times more carbon than those built to the latest building regulations but every pound you spend on increasing the energy efficiency of new build beyond Level 3 of the new Code for Sustainable Homes would typically save 50 times more carbon if it was spent on improving the existing stock."
 
Colley said the current programme of incentives is far too limited and uncoordinated. He said: "Phase II of the Energy Efficiency Commitment has been so heavily subscribed that we now have a hiatus until Phase III starts some time next year.  But the golden opportunity is there with the introduction of new Energy Performance Certificates. House purchasers will be given a very clear picture as to how to improve the energy efficiency of the property they are buying."
 
He added: "What government needs to do is to provide them with the incentive to act on the basis of that independent report by offering some form of tax break or grant if, within a year of moving in to their new home, they invest in the improvement measures identified in these certificates."