Lower VAT rates already apply to the installation of some energy saving materials and micro generation systems.

But the campaigners want to see the 5% rate apply to all Green Deal measures which would improve the performance of existing buildings.

A letter to ministers states: “The Green Deal has the potential to play a central role in the transition to a green economy by cutting carbon, protecting households from increasing energy costs and creating new jobs.

“The Government must prepare for the Green Deal by stimulating further demand in the energy saving market.

“Without an additional package of incentives few owners and occupiers are likely to take action to improve the energy efficiency of their buildings, even if the upfront costs are met by Green Deal finance.

“Therefore, we urge MPs from all parties to ask the Government to levy VAT at a rate of 5% for all Green Deal approved measures.”