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Daventry, Northamptonshire

Single-storey rear extension in Daventry

For homes in Daventry, a single-storey rear extension is often the simplest way to gain space without moving. Ground-floor space across the back of the house, usually for a kitchen, dining or family room. We take it from survey to completion certificate.

We cover Daventry (NN11) as part of our Northamptonshire work. A single-storey rear extension in Daventry is mostly built from the garden side, so the house stays usable for most of the job.

Book a free site visit

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

How much does a single-storey rear extension cost in Daventry?

Guide prices for a single-storey rear extension in Daventry start from our East Midlands rate of £1,840–£3,010 per square metre, including VAT. East Midlands prices sit a little below our West Midlands baseline.

Single-storey rear extension prices in Daventry
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£22,000–£36,000
4 m wide × 5 m deep (20 m²)£37,000–£60,000
4 m wide × 6 m deep (24 m²)£44,000–£72,000

Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.

Do you need planning permission for a single-storey rear extension in Daventry?

Planning for a single-storey rear extension in Daventry follows the English householder rules.

In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.

England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.

What are homes in Daventry like to extend?

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

How a single-storey rear extension in Daventry comes together

  1. Survey visit

    We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.

  2. Drawings and budget

    Floor plans and elevations for the options, each with a guide price.

  3. Planning and regulations

    We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.

  4. Fixed price and build

    A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.

Single-storey rear extensions near Daventry

We also build single-storey rear extensions in nearby Rugby (9.0 miles) and Northampton (11.7 miles).

Other work in Daventry:

All rear extensions in Daventry

FAQ

Single-storey rear extension questions in Daventry

Can I get a price without a visit?

Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.

Who will build my extension?

Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.

Does it add value to the house?

Nationwide's October 2025 house price research found that a 10% increase in floor area is linked to about 5% higher value on average. It is a guide, not a promise; local agents can tell you what extended homes on your street sell for.

Is the site visit in Daventry free?

Yes. We visit, measure up and talk through the options with no cost and 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.

Do I need planning permission for a rear extension in Daventry?

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.

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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