The cost of home improvements could double if professional builders have to solve botched DIY jobs first, a building expert has warned.
Harvey Ellingham, boss of Home Improvements Guarantee, said that pride often led to DIY disasters at this time of year.
A survey, by the Nationwide Building Society, suggests that DIY projects cost an average of £3,342.
But one expert told BBC News that enthusiasts often overspent.
Jo Behari, a former City worker who founded Home Jane, a team of handywomen and home improvement specialists, said that spring was a good time to look out for bargains.
This time of year is the most popular for homeowners to start DIY projects.
The Nationwide survey suggested that nearly half of those asked were planning a project and were willing to spend thousands of pounds.
This average bill increased for the older generation, with those aged over 55 spending £4,045.
Richard Napier, director for savings and mortgages at the Nationwide, said there was an "appetite" for people to invest in their homes.
However, 7% of people aged 18 to 24 were willing to use a credit card to fund this work, with another 4% happy to turn to payday loans to finance it.
Mr Ellingham, who has been in the building trade for 20 years, said that people risked a big bill by failing to do their homework.
Overlooking an extension being built by professionals at a home in Sutton, west London, he said that people risked damage to their homes and their health if they did not plan DIY work sufficiently.
"If you are going to put a nail into a wall, you need to know what is behind that wall. If you are going to put a nail into the floor, you need to know whether there are pipes under there," he said.
"It is common sense, but some people believe they know what they are doing and go full-steam ahead."
But mistakes are not just made by people who only work on their own homes. A survey by the TrustMark accredited trader scheme found that incompetent tradesmen have cost UK homeowners an estimated £1.9bn over the last year.
Ms Behari said that some DIY enthusiasts failed to learn the basics about their home and were too embarrassed to admit they had a problem.
She also said that people did not need to spend as much as they did at this time of year.
- Looking online for free guides about basic DIY work
- Searching for bargains during holiday weekends in home improvements stores
- Spending a sensible amount on tools. For example, a £50 electric drill was sufficient for most homeowners
"Make sure you don't buy ridiculously expensive tools; I know it is easy to get carried away," she said.