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Tilbury, Essex

Semi-detached rear extension in Tilbury

We plan and build rear extensions for semi-detached houses for homeowners in Tilbury. Single or two-storey extensions for semi-detached houses, with side access and one party wall. Start with a free site visit, then a written price once the design is agreed.

We cover Tilbury (RM16, RM17 and RM18) as part of our Essex work. In Tilbury we measure the attached neighbour's extension at the survey, because it often sets the sensible depth for yours.

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 semi-detached rear extension cost in Tilbury?

A semi-detached rear extension in Tilbury is priced at £2,010–£3,290 per square metre including VAT as a guide, before kitchen fit-out and fees. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.

Semi-detached rear extension prices in Tilbury
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

Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.

Do you need planning permission for a semi-detached rear extension in Tilbury?

The planning route for a semi-detached rear extension in Tilbury is set by England's householder rules and your council.

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.

A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.

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 Tilbury like to extend?

Post-war semis and newer estates are typical of Tilbury, 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 semi-detached rear extension in Tilbury comes together

  1. Free site visit

    We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.

  2. Drawings and budget

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

  3. Paperwork handled

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

  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.

Semi-detached rear extensions near Tilbury

We also build rear extensions for semi-detached houses in nearby Gravesend (1.5 miles) and Grays (1.7 miles).

Other work in Tilbury:

All rear extensions in Tilbury

FAQ

Semi-detached rear extension questions in Tilbury

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.

Do you handle building control in Tilbury?

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

Single or two-storey on a semi?

Two-storey if you need bedrooms, single-storey if you need a bigger kitchen. Planning risk is lower for single-storey.

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.

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.

Is the site visit in Tilbury free?

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

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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