Britons are paying out an extra £529 million to fix bodged jobs by untrustworthy tradespeople, according to new research from Direct Line Home Insurance.

In the past year alone, more than half a million Britons – one in 50 of those who have had work carried out - were forced to employ a second tradesperson to repair recently completed but botched jobs. These unlucky Britons have each shelled out an extra £955, on average, in the process.

36 per cent of those surveyed needed the original tradesperson back to correct their own work, while 26 per cent have had to live with the damage for some time before they could afford to fix it.

Among the tradesmen who have carried out substandard work for these dissatisfied Britons are carpenters (11 per cent), builders (8 per cent), plasterers (8 per cent) and electricians (7 per cent).

From unsafe electrics to leaking roofs, this substandard work has added significantly to the £33 billion already spent on home repairs in the UK in the past two years.

Four in 10 (37 per cent) dissatisfied customers suffered substandard work as the jobs were delegated by busy tradespeople to unqualified or inexperienced workers while one in 10 reported that tradespeople caused more damage than they had repaired.

More than one in four Britons (26 per cent) delayed repair work as they were unsure of whom to trust.

Andrew Lowe, head of home insurance, Direct Line, said, "Our research confirms that poor workmanship and few guarantees are causing unnecessary expense and inconvenience for many homeowners, and even worse still, may result in making their homes unsafe."

Direct Line recommends taking the following steps to safeguard against untrustworthy tradespeople:

• Contact your insurer for a tradesperson recommendation
• If possible, get recommendations of reliable tradespeople from friends or family
• Ensure any tradesperson you employ is a member of a reputable trade association
• Ask the tradesperson for client references before agreeing to any work
• Always get an estimate before work commences
• Only make a part payment in advance of work commencing, with final payment made on completion
• Before commencing work, get written guarantee from the tradesperson

If you are unhappy with a tradesperson's services, Direct Line recommends the following:

• Advise the tradesperson of your concerns immediately
• If this does not work, put your complaint in writing
• If there are still problems, consult the Citizens Advice Bureau, Trading Standards or the relevant Trade Association