The government has set out the restrictions on its Green Homes Grant in documents published today.

The scheme announced last month promised to give home owners grants to cover two thirds of the cost of energy saving home improvements up to a maximum of £5,000.

For low income households it promised to cover 100 per cent of the cost of energy efficiency upgrades up to a maximum of £10,000.

However, documents published by the government today lay bare restrictions which mean that home owners may get much less than they had hoped.

The scheme sees different types of energy efficiency measures divided into two categories: “primary” and “secondary”.

In order to qualify for funding to cover secondary measures, home owners must first carry out one of the measures on the primary list.

Furthermore, the amount of money offered by the government for secondary measures is capped at the amount the home owner claimed for primary improvements, so if you receive £1,000 towards primary upgrades, you will only get £1,000 towards any secondary steps you wish to take.

The list of “primary” measures covers different types insulation, including cavity, solid wall, under-floor and roof.

The primary list also includes the installation of low-carbon heating systems such as air source heat pump, ground source heat pump and solar thermal.

It means that home owners must choose one of the above measures in order to qualify for help with “secondary” improvements, which include draught-proofing, double or triple glazing, fitting energy-efficient doors, installing thermostats and heating controls, insulating hot-water tanks.

The government confirmed today that tradespeople carrying out the work for those using the grant scheme would need to be TrustMark accredited.

Later this month, home owners across England will be able to access advice and support on improving the energy efficiency of their homes from the Simple Energy Advice service. 

SEA will suggest appropriate home improvements that homeowners may be able to apply for support in funding.

Business and energy secretary Alok Sharma says: “Green home improvements will save people money on their energy bills, help to cut carbon emissions, and create new work for many thousands of builders, plumbers and other tradespeople.

“Our TrustMark scheme will guarantee that building work is completed to a high standard by accredited tradespeople, ensuring consumers are fully protected.”