A survey has revealed that tradesmen cause up to £590 million of damage to homes in Britain every year.
And with one in five tradesmen believed to be working without any public liability insurance, the survey from Sainsbury's warns that up to £118 million of this damage may not be covered by insurance.
There has also been a 5% increase in the past year in the number of personal loans the bank is approving to pay for home improvement.
While up to 25 million British adults have employed a tradesman to carry out work in their home in the last five years, only 16% (4 million) asked for evidence of public liability cover from the person they were employing before the work began.
Some 84% say they didn't ask or couldn't remember doing so, and nearly one in five (19%) said they didn't ask for evidence of insurance because they didn't know about the cover.
The British Insurance Brokers Association (BIBA) has called for public liability insurance to be made compulsory.
© Press Association 2010