Documents published by the Department for Communities and Local Government show that there is no intention to implement Part L changes this year, despite earlier Government commitments that they would be introduced in October 2013.

It is now believed that the changes will come into effect six months later than previously expected, in April 2014.

Knauf Insulation is warning that delays will be grave implications for the drive towards zero carbon homes.

John Sinfield, Managing Director of Knauf Insulation Northern Europe, said: “This delay is yet another example of the ‘greenest government ever’ dragging its feet when it comes to making any real or decisive changes towards improving the energy efficiency of the UK’s housing stock.

“Indeed, the whole timescale for achieving zero carbon is in danger of being derailed by Government delays and setbacks.

“On top of that, the revisions are meaningless in a housing market where it is still possible to buy a house that is built to 2003 standards.

“As new buildings are constructed to planning legislation put in place several years earlier, perhaps we should really be asking ourselves whether we will see any homes built to zero carbon standards before 2020?

“If the Government is truly serious about meeting its carbon reduction obligations then decisive action needs to be taken to improve the efficiency of ALL the UK’s housing stock, both new build and refurbishment.

“The could be achieved by removing the need for a Green Deal provider signature to access retrofit cash back incentives or introducing other ‘demand drivers’ such as linking Stamp Duty to the property’s energy efficiency performance.”