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Blackheath, Greater London

Kitchen-diner rear extension in Blackheath

We plan and build kitchen-diner rear extensions for homeowners in Blackheath. An open-plan kitchen, dining and family room that opens straight onto the garden. Start with a free site visit, then a written price once the design is agreed.

We cover Blackheath (SE3, SE10 and SE13) as part of our Greater London work. For Blackheath kitchens we plan the extraction route and the island drainage before the slab is poured, so nothing has to be chased in later.

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 kitchen-diner rear extension cost in Blackheath?

A kitchen-diner rear extension in Blackheath is priced at £2,470–£4,030 per square metre including VAT as a guide, before kitchen fit-out and fees. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.

Kitchen-diner rear extension prices in Blackheath
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£29,500–£48,500
4 m wide × 5 m deep (20 m²)£49,500–£80,500
4 m wide × 6 m deep (24 m²)£59,500–£96,500

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 kitchen-diner rear extension in Blackheath?

The planning route for a kitchen-diner rear extension in Blackheath 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.

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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.

What are homes in Blackheath like to extend?

Much of Blackheath is Victorian and Edwardian terraced housing with narrow back additions, which suits side returns, wraparounds and 3 metre rear extensions. Many streets are in conservation areas, gardens are short, and almost everything comes through the house or along a rear alley.

How a kitchen-diner rear extension in Blackheath 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. Approvals

    Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.

  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.

Kitchen-diner rear extensions near Blackheath

We also build kitchen-diner rear extensions in nearby Lee (0.6 miles) and Kidbrooke (0.8 miles).

Other work in Blackheath:

All rear extensions in Blackheath

FAQ

Kitchen-diner rear extension questions in Blackheath

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.

Can I live at home while the extension is built?

Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.

Do you fit the kitchen?

Yes, whether you buy it yourself or we supply it. We take the measurements from the built shell, not the drawings.

Can you match the brick or stone on my Blackheath house?

We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.

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.

What postcode areas do you cover around Blackheath?

Including SE3, SE10 and SE13, and the surrounding Greater London 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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