There are also proposals to fund improvements recommended in Energy Performance Certificates through green mortgages - something Defra is currently discussing with the financial services industry.
Launching the consultation, communities secretary Ruth Kelly said: "This is an important opportunity to improve the buying and selling process for consumers.
"We want to promote a greener housing market for consumers and Energy Performance Certificates can play a key part in this. By providing more information on the energy efficiency of homes, we can help consumers make more informed choices about the homes they buy and their impact on climate change."
Housing minister Yvette Cooper said: "Most people have no idea about things like the lagging in the loft when they buy a new home.
"But this will tell people how they can save money on their fuel bills and cut their carbon emissions at the same time. The trials have also shown we need to tackle the unfair postcode lottery in searches which can cause homebuyers all kinds of costs and delays."