The DIY mistakes that take thousands to fix – and knock value off your home

If you're planning on doing DIY this summer, you will want to think twice about the jobs that can cost you thousands to repair if they go wrong. What's more, some of these botched DIY projects can also knock a lot of value off your home, making them especially disastrous if you're planning to sell. 

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According to Google trends, there was a 59 percent and 21 percent increase in search volumes for house DIY during the first and second lockdowns. What’s more, it’s reported that 61 percent of homeowners have carried out DIY projects during lockdown. But while some jobs are cheaper and easier to do on a DIY basis, others really should be left to professionals. 

The DIY mistakes that will cost the most to repair

The experts at HomeHow.co.uk asked 3,142 households what projects they have undertaken in the past year and discovered the costliest DIY jobs to rectify.

The priciest DIY job to rectify is knocking down a wall. DIYers should always call in an expert to determine whether the wall they intend to knock down is structural. This issue could cost homeowners well over £20,000 for a professional to sort out due to the possibility of the house collapsing - in comparison to a free quote.

The second most costly DIY job to fix is electrical wiring - it could cost more than £2,000 to rewire in addition to being extremely dangerous. If this job is done to an inadequate standard, an electrician may have to be called out to rewire the entire house system! Examples of poor wiring include frayed wires, loose connections, and excessive heat.

Fitting flooring isn’t as easy as it looks and if done incorrectly, it may cost around £1,200 to refit. Floor surfaces can look rough and uneven when materials like nails and glue are left behind, which also decreases longevity.

Planning on fixing a radiator or repainting and tiling walls? Be sure you know what you're doing. Cracked tiles are a common example of a poor finish, as well as bumpy grouting, and could cost homeowners £450 to fix. The expense covers new materials and labour charge, so it is best to get it right the first-time round!

Which DIY mistakes will reduce the value of a home?

Lisa Evans, property expert at HomeHow, said that you really, really should avoid knocking through walls yourself. Not only will it be expensive to fix, but it will also knock value off your home: 'This job can actually reduce the value of your home if the wall is between two bedrooms. For example, if you want to merge two small bedrooms into one, this may not be the best idea, as this can decrease property value by 20 percent. If you plan on knocking down a wall to accommodate an extension but do not obtain planning permission, this could actually lower the price of your home by 15 percent.'

Forewarned is forearmed: if it's a big structural job, leave it to the pros.