Rear extension design, approvals and build across the UKCall 0800 088 6341 · Online guide price
Rear Extensionsrear-extensions.co.uk 0800 088 6341 Get a guide price

Upminster, Greater London

Kitchen-diner rear extension in Upminster

We plan and build kitchen-diner rear extensions for homeowners in Upminster. 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.

Upminster and its postcode districts RM11, RM12 and RM14 are part of our Greater London coverage. For Upminster 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 Upminster?

In Upminster, our guide for a kitchen-diner rear extension is £2,470–£4,030 per square metre including VAT for a standard specification. 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 Upminster
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

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 kitchen-diner rear extension in Upminster?

Here is how the rules in England apply to a kitchen-diner rear extension in Upminster.

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. 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 Upminster like to extend?

Much of Upminster is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.

How a kitchen-diner rear extension in Upminster 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. 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.

Kitchen-diner rear extensions near Upminster

Close by, we work in Emerson Park, about 1.7 miles away, and Hornchurch, about 1.7 miles away.

Other work in Upminster:

All rear extensions in Upminster

FAQ

Kitchen-diner rear extension questions in Upminster

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.

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.

Can I add a utility room?

Often. A narrow utility or boot room along one side keeps the washing machine out of the open-plan space.

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

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.

Is the site visit in Upminster free?

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

How long does a rear extension take to build in Upminster?

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

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.

CallGuide price