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Northamptonshire

Rear extensions in Brackley

From the first measured visit to building control sign-off, we handle rear extensions in Brackley under one contract.

Brackley is in Northamptonshire, with postcode districts including NN13. The nearest places we also cover are Buckingham (7.3 miles) and Banbury (8.4 miles).

Book a free site visit

Tell us about the house and we'll call to arrange a free, no-obligation visit.

Rear extensions we build in Brackley

Also available across Northamptonshire:

Rear extension prices in Brackley

East Midlands prices sit a little below our West Midlands baseline.

ExampleGuide inc VAT
Single-storey, 3 m × 4 m (12 m²)£22,000–£36,000
Single-storey, 4 m × 6 m (24 m²)£44,000–£72,000
Two-storey, 3 m × 5 m footprint (30 m²)£52,500–£78,500
Side return, about 14 m²£31,000–£51,500
Wraparound, about 25 m²£53,500–£87,500

What are homes in Brackley like to extend?

Brackley has plenty of inter-war semis and bungalows, and single-storey rear extensions suit both.

Planning rules for Brackley

Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.

If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.

Every rear extension in England needs Building Regulations approval, whether or not planning is needed. You can use the council's building control service or a registered building control approver, by full plans (checked before work, usually within five weeks) or a building notice, and you get a completion certificate at the end.

Nearby towns

FAQ

Questions people ask

How much is a rear extension in Brackley?

A 3 m × 4 m single-storey rear extension is about £22,000–£36,000 including VAT at our East Midlands guide rates; the written price follows a survey.

Do I need planning permission in Brackley?

Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.

Is the site visit in Brackley free?

Yes, with no obligation.

Do I need a party wall agreement?

In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

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