DEVASSIST: Planning Permission

Planning Permission: What Happens If Your Neighbour Wants to Extend Their Property?

When you buy a home, it’s easy to focus on what you see when you first get a look at the property. But the biggest changes to your living environment can often happen next door. 

A neighbour’s extension can massively shift your privacy, sunlight, noise levels and even the property’s long-term resale value, so it’s worth understanding how the process actually works before you commit to a purchase.

Not every extension needs planning permission

Many smaller home extensions fall under what’s known as permitted development. This means a neighbour can carry out certain types of building work without submitting a full planning application, as long as they stay within strict size and design limits set by national legislation.

Because of this, you won’t always get a say, or even a warning, when neighbouring homes are extended. If you’re buying on a street where many houses already have lofts, large rear additions or outbuildings, it can be a sign of what future neighbours may also be able to build.

If planning permission is needed, you’ll usually be notified

For extensions that do require permission, the local planning authority normally notifies nearby residents. This is typically done by letter or by putting up a notice near the site, giving you a short window to submit comments.

You can raise concerns about matters such as loss of light, overlooking, overshadowing, noise or the overall appearance of the proposal. However, the council can still approve the extension if it meets planning policy, even when neighbours object.

Extensions can impact more than privacy

Most people worry about losing light or being overlooked, but the effects of an extension can be wider than that. Construction can cause months of disruption. Garden overshadowing, increased noise, pressure on parking or a change in the feel of the street can also follow once the work is completed. These aren’t things most buyers consider at the offer stage – but they can make a meaningful difference once you move in.

Planning history gives you clues about what might happen next

If you want to understand the potential for change, the local planning history is one of the most useful indicators. Patterns such as repeated applications, withdrawn proposals or a street full of extended properties suggest an area where development is common, and more is likely.

This is an area where homebuyers often feel under-prepared, because standard conveyancing searches don’t analyse future development potential or policy context.

Why this matters before you buy

By the time your neighbour applies for permission, your options are limited. Understanding the planning context before you exchange contracts means you’re not caught off-guard by changes that could affect the way you use and enjoy your home.

At DevAssist, we specialise in helping buyers see the full picture – including planning activity, development patterns and the policies shaping what could be built around your future home. 

Our reports give you clarity that standard searches don’t, so you can make your purchase with confidence rather than uncertainty.

If you’re considering a move and want to avoid unpleasant surprises from neighbouring development, we’re here to help.

Kindly shared by DevAssist