Bodges, botches, bungles and blunders. Sadly, things can go wrong in home improvement projects. Especially if you’ve never planned an extension or renovated a home before.
But the good news is that disasters can be dodged, and your home honed without hiccups, if you avoid these basic but all too common mistakes.
Failing to plan
It’s vital to know exactly what you want to achieve before you start. Do you want to create more living space, upgrade your surroundings or boost your home’s value?
Think about the best ways to accomplish your aims. What are your options and what are the pros and cons?
If you’re planning a loft or garage conversion, for example, consider whether you’ll be losing precious storage room.
On the other hand, if you’re planning an extension, consider whether you’ll be losing valuable garden. You don’t want to lose your favourite sunbathing spot.
Meanwhile, if you’re renovating to add value to your home, consider what return on investment you’ll get. Every street has a price ceiling.
You’ll also need a team of professionals you can rely on. These might include:
- a builder
- a plumber
- an electrician
- a roofer
- a designer
- a structural engineer
- a surveyor
- building control specialist.
Tell them exactly what you want and don’t change your mind halfway through the job. It could cost you a fortune. Which brings us nicely to…
Underestimating costs
Home improvements have a habit of running over budget. So, don’t be a hapless homeowner who begins a project and then runs out of money.
Here are some of the key things you’ll need to budget for:
- materials
- labour
- professional fees.
Materials includes everything from bricks, wood, steel, and plasterboard to fittings like light switches, radiators, taps, tiles, flooring and much, much more.
Labour costs can vary depending on your postcode and how in-demand your contractor is. Make sure you get at least 3 quotes.
Professional fees are something first-time home improvers sometimes forget. So, remember to set aside money for structural engineers, interior designers, and even building control (who sign off the job as safe).
If all this seems overwhelming, try hiring a quantity surveyor to list everything you need and price it up. You could even put the job out to tender. Then you’ll get a fixed price for all the work in one.
However, even fixed costs can go up if there are unforeseen problems. So, leave a healthy contingency. Our partners HiiGuru suggest 10-15% of your budget, in case you have some bad luck.
Also think about where you’ll get the money from. For example, you could apply for a home improvement loan. Or, if you’re one of our mortgage customers, you could think about borrowing more to fund your project.
Remember, when it comes to budgeting, being cautious is better than ending up in debt. Or, even worse, in a half-finished home with no roof and an ensuite rainwater shower.
Forgetting about planning permission
Did you know that you might have to tear home improvements down if you do them without permission?
Although you can sometimes apply retrospectively – in other words, after the job’s done – you might not be successful.
And you might need to explain why you didn’t get permission in the first place. Hint: saying ‘the dog ate my application’ won’t fool anyone.
Fortunately, you can do some projects using ‘permitted development rights’. This means you can bypass full planning if your extension or conversion meets certain conditions. Here’s a quick summary of permitted development rules.
It’s important to remember that the rules aren’t simple, though. So talk to your Local Planning Authority before you begin. You could even try to get a lawful development certificate to confirm your project’s legal.
After all, the last thing you want is to upset the neighbours, breach a restrictive covenant, or break the terms of your lease.
Ignoring building regulations
Building regs make sure home improvements are safe and meet modern standards. They’re a set of rules covering stuff like fire safety, sound, insulation, ventilation, hygiene, electrical safety and waste disposal.
They also make sure your building work follows a structural design. In other words, that the roof and walls are all supported and won’t collapse like a house of cards.
During the work, an inspector will come and check that everything’s being done right. And they could refuse to sign it off if your builder cuts corners. This could be a big problem when you decide to sell up. Potential buyers will want to know that building regulations were followed. After all, wouldn’t you?
Because building regs can be complicated, you might need a surveyor to help you out – especially if you’ve made our final mistake…
Hiring a rogue trader
Most builders are highly skilled and honest as a ladder is long. But sadly, there are some bad apples out there. And they’re not always easy to pick out.
These are often telltale signs:
- they’re much cheaper than other builders
- they can start straight away
- they want a large cash advance
- they’ve got past county court judgements (CCJs) or bankruptcies.
Although it’s tempting to go for the lowest quote, it’s usually lower for a reason: maybe the builder forgot to include something important? Or maybe they don’t intend to honour your agreement?
Sadly, rogues often price low just to win your business and pocket the deposit. They might even start the job, turn up for a few days, and then disappear for weeks.
What’s more, they could walk off the job as soon as their money runs out. And that means you’ll need to pay someone else to finish it. You might even have to pay extra to correct their mistakes.
So, always ask for references before you choose a builder. Visit properties they’ve worked on. Talk to the owners. And search TrustOnline to see if they have any judgements, orders, or fines against them (there’s a small fee for this). It’s also worth checking they’ve got public and employers’ liability insurance.
And be careful if a cheeky chappie smiles at you and promises to start tomorrow. Most good builders are usually booked up weeks in advance.
If in doubt, get help!
Planning home improvements isn’t easy. So, unless you’ve got lots of experience or know a builder you trust, it could be worth hiring an architect.
Architects understand all the different stages of home improvements – from planning permission to project management. They can even help you find other professionals like a structural engineer.
Meeting building regulations is also easier with an architect. They know building projects inside out, can organise a team and keep a job on track. They’ll also have an inkling about whether your budget is big enough.
Of course, there’s another big thing good architects can help you with: design. They’re experts at maximising space, increasing natural light and making sure your home looks fantastic.
This all adds up to fewer bodges, fewer botches, and less chance of bumps in the road.
This content was accurate when published on 21/04/26.
If you’re thinking about improving your home, check out My Home Manager. You’ll find a handy home improvements handbook to keep you on track. Meanwhile, if you’re looking for funding options, don’t forget to read about our home improvement loans.