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Chafford Hundred, Essex

Single-storey rear extension in Chafford Hundred

Thinking about a single-storey rear extension in Chafford Hundred? Ground-floor space across the back of the house, usually for a kitchen, dining or family room. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.

Chafford Hundred sits in Essex, with postcode districts including RM15, RM17 and RM20. A depth of 3 to 4 metres keeps many single-storey rear extensions in Chafford Hundred within permitted development, subject to the house's planning history.

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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 Chafford Hundred?

For Chafford Hundred we work from the East of England rate: £2,010–£3,290 per square metre of new floor, including VAT, standard specification. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.

Single-storey rear extension prices in Chafford Hundred
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£24,000–£39,500
4 m wide × 5 m deep (20 m²)£40,500–£65,500
4 m wide × 6 m deep (24 m²)£48,500–£79,000

We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.

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

Whether your single-storey rear extension in Chafford Hundred needs a planning application depends on its size, your house and any local restrictions.

English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres 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.

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 Chafford Hundred like to extend?

Post-war semis and newer estates are typical of Chafford Hundred, and many have room for a full-width extension. Shrinkable clay is common in the East of England, so foundations near trees and hedges are designed to NHBC-style depth guidance.

How a single-storey rear extension in Chafford Hundred comes together

  1. Look round and measure

    A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.

  2. Options and costs

    We draw layout options and price each one, so the budget shapes the design rather than surprising you later.

  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. Written price, then build

    Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.

Single-storey rear extensions near Chafford Hundred

Neighbouring places we cover include South Ockendon (1.4 miles) and Grays (1.6 miles).

Other work in Chafford Hundred:

All rear extensions in Chafford Hundred

FAQ

Single-storey rear extension questions in Chafford Hundred

Do I need planning permission for a rear extension in Chafford Hundred?

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.

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.

How deep can a single-storey rear extension be without planning?

In England, 3 metres on an attached house and 4 metres on a detached house under permitted development, or up to 6 and 8 metres with prior approval. Wales allows 4 metres; Scotland and Northern Ireland have their own limits.

How long does a rear extension take to build in Chafford Hundred?

Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.

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

As a guide, £2,010–£3,290 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £24,000–£39,500 at that rate. Your written price follows the survey.

What postcode areas do you cover around Chafford Hundred?

Including RM15, RM17 and RM20, and the surrounding Essex area.

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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