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Southend-on-Sea, Essex

Single-storey rear extension in Southend-on-Sea

For homes in Southend-on-Sea, 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.

Southend-on-Sea and its postcode districts SS0, SS1, SS2 and SS3 are part of our Essex coverage. A depth of 3 to 4 metres keeps many single-storey rear extensions in Southend-on-Sea within permitted development, subject to the house's planning history.

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 Southend-on-Sea?

In Southend-on-Sea, our guide for a single-storey rear extension is £2,010–£3,290 per square metre including VAT for a 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 Southend-on-Sea
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

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 Southend-on-Sea?

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

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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.

What are homes in Southend-on-Sea like to extend?

Post-war semis and newer estates are typical of Southend-on-Sea, 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 Southend-on-Sea 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. Options and costs

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

  3. Paperwork handled

    Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.

  4. Build and sign-off

    We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.

Single-storey rear extensions near Southend-on-Sea

From Southend-on-Sea, the nearest places we also cover are Rochford (3.1 miles) and Hadleigh (4.6 miles).

Other work in Southend-on-Sea:

All rear extensions in Southend-on-Sea

FAQ

Single-storey rear extension questions in Southend-on-Sea

Do I need planning permission for a rear extension in Southend-on-Sea?

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.

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.

Can I stay in the house during the build?

Usually yes. The noisiest, dustiest stage, removing the back wall, is kept to the final weeks and screened off. Most families set up a temporary kitchen elsewhere in the house.

Do you handle building control in Southend-on-Sea?

Yes. We apply to the council or a registered building control approver and hand over the completion certificate.

Is the site visit in Southend-on-Sea free?

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

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.

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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