Home extensions in Northolt

Popular extension prices in Northolt

Use these Northolt guide prices to sense-check a budget; the guide-price tool narrows them to your own size, and the site visit turns them into a written figure.

What works best for Northolt houses?

In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.

For many houses here, wraparound extensions, glass box extensions or side return extensions gives the most useful space for the budget.

Do extensions in Northolt need planning permission?

In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.

In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.

In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.

If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.

Applications are decided by the local planning authority (your district, borough or unitary council).

Covering Northolt and nearby

We cover Northolt and the postcode districts HA2, UB5, UB6. Neighbouring towns we cover include Greenford (1 mile), South Ruislip (2 miles), Harrow (3 miles), Southall (3 miles), Ruislip (3 miles). For homes towards Hertfordshire, Bushey is around 7 miles away.

• Greenford
• South Ruislip
• Harrow
• Southall
• Ruislip