Tradesmen are causing around £600 million of damage to British homes each year, builders liability insurance holders have been told.
New research from Sainsbury's Home Insurance showed that up to £120 million of this damage might not be covered as one in five people working in the trades are estimated to be operating without any public liability insurance.
Furthermore, the data found that while 25 British homeowners have employed someone to carry out work on their home in the last five years, only 16 per cent have asked for evidence of public liability cover.
Ben Tyte, Sainsbury's home insurance manger, said: "All homeowners have a duty of care to look after their properties and if no effort to check for public liability cover is made and damage is done, they could find their home insurance invalidated and risk having to pay for major repairs themselves."
The need for builders liability insurance was highlighted earlier this month, when TMN Fabrications was prosecuted after a worker fell from a roof.