At least a dozen MPs, including Greg Barker, Minister for Energy and Climate Change, have agreed to back Building Products' call for energy-efficient windows to be included in the Government's Green Deal. The Green Deal is central to the Government's plan for improving the energy efficiency of homes. Under the deal, householders will be offered loans by retailers/installers to cover energy saving measures installed in their homes. The loan will stay with the house, passing from owner to owner, and will be paid back through savings on the energy bills. The Deal's "Golden Rule" is that, in order to be eligible, the installation concerned must result in sufficient savings to pay off the initial cost within the life time of the deal. The Green Deal is scheduled to come into operation in 2012 and the precise details of what will be included are still being thrashed out. Building Products is working with the GGF to explain just how much difference energy-efficient windows can make: Up to 23% of a home's energy can be lost through inefficient windows; Installing Energy-Efficient Windows (EEW) would reduce both national CO2 emissions and domestic energy expenditure by around 10%; Converting all existing housing stock to EEW would save nearly 4M/t carbon, 14.5M/t CO2 and £2.4BN/pa on energy bills; The process of installing the windows would create up to 10,000 jobs.