You’ve run out of space. The kids are growing. You’re working from home. The kitchen’s cramped.
You want more room, but moving is expensive and the market’s a mess. So you start looking at extensions, like those on this site.
It sounds simple: knock down a wall, add a room, carry on with life. But if you skip the wrong detail, it can cost you thousands — and land you in legal trouble.
Here’s what you need to know before you pick up the phone.
You Might Need Planning Permission
Not every extension needs it. Some fall under permitted development, like small single-storey rear extensions.
But the moment you build upwards, go too wide, or live in a conservation area, you’re into planning territory.
Fail to get approval and you could be ordered to tear it down. Yes, even if it’s already built.
Always check first. We can help you speak to the council — click here to contact us.
You’ll Need Building Regulations Approval
Planning permission is one thing. Building regs are another.
Even if your extension doesn’t need planning, it still has to meet structural and safety standards. That includes:
- Fire safety
- Drainage
- Insulation
- Roof structure
- Foundations
It’s not optional. You’ll need an inspection. And if it fails, your insurance might not pay out — and your home’s value could drop.
Budget Creep Is Real
You start with a number in your head. Then the builder finds pipes that need moving. The architect adds a rooflight. The skip costs more.
Most people underestimate the cost. They forget to include:
- Planning fees
- Architect drawings
- Structural engineer reports
- VAT
- Kitchen or bathroom fitting
Price it all first. Add a buffer. Then decide.
Your Neighbours Might Object
Building near a boundary? You may need to serve a Party Wall Notice.
If your work affects a shared wall or structure, your neighbour has a legal say. Ignore it, and they can stop the build, or take you to court.
It’s not about being difficult. It’s the law. We can help handle it properly.
It Takes Longer Than You Think
Bad weather. Missed deliveries. Slow council replies.
Most extensions take longer than the first quote. Some run months over. If you’re living in the house, it can be noisy, messy and stressful.
Plan for the mess. Talk to your builder about timing. And don’t schedule a family visit during the build.
You’ll Need the Right Team
This isn’t a job for a mate with a van and a hammer. You’ll need:
- An architect or building designer
- A builder with experience in structural work
- Possibly a project manager
- Maybe a surveyor or engineer if you’re going up or out
The cheapest option isn’t always the safest. Check reviews. Ask for proof of insurance. Get it in writing.
Don’t Rush the First Step
A good extension adds value and space. A bad one adds stress and regret.
The early planning is where most people go wrong. They skip details. Trust vague advice. And end up stuck halfway through a job they can’t finish.
We’ve built hundreds of extensions. We know what works — and what catches people out.