If offers reputable tradesmen the opportunity to clearly separate themselves from the cowboys

Industry minister Brian Wilson

The scheme was launched at the Ideal Home Show in London on Tuesday.

It has already been successfully piloted in the Midlands and Somerset.

It will be rolled out across the country over the next three to four years.

Customers can check the credentials of builders by calling a low cost telephone number or tapping into a new website.

'Peace of mind'

Industry minister Brian Wilson said this had been long-awaited by consumers.

"The quality mark brings peace of mind for consumers by providing, for the first time, a government-backed assurance of quality work.

"If offers reputable tradesmen the opportunity to clearly separate themselves from the cowboys".

Already 160 companies have achieved the quality mark.

And 30,000 consumers have used the service to check the credentials of builders.

Paul Weston, of Age Concern, welcomed the new scheme.

"It only costs the price of a local call and you're then provided with a list of reputable tradespeople in your area."

Find the quality mark website at www.qualitymark.org.uk or call the hotline on 0845 300 8040.