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Lee, Greater London

Kitchen-diner rear extension in Lee

For homes in Lee, a kitchen-diner rear extension is often the simplest way to gain space without moving. An open-plan kitchen, dining and family room that opens straight onto the garden. We take it from survey to completion certificate.

Lee and its postcode districts SE3, SE12 and SE13 are part of our Greater London coverage. A kitchen-diner is often the reason people in Lee extend: the back kitchen in period terraces and mansion flats is rarely big enough for a table.

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 Lee?

For Lee we work from the London rate: £2,470–£4,030 per square metre of new floor, including VAT, 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 Lee
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

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 kitchen-diner rear extension in Lee?

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

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.

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 Lee like to extend?

Period terraces in Lee sit alongside flats, and the difference matters: houses usually keep permitted development rights, while flats and maisonettes need planning permission for any rear extension.

How a kitchen-diner rear extension in Lee 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. Design and guide price

    Two or three layout options with a guide price for each, so you choose the design knowing what it costs.

  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. 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 Lee

Close by, we work in Blackheath, about 0.6 miles away, and Ladywell, about 1.2 miles away.

Other work in Lee:

All rear extensions in Lee

FAQ

Kitchen-diner rear extension questions in Lee

What postcode areas do you cover around Lee?

Including SE3, SE12 and SE13, and the surrounding Greater London area.

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

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.

How big should a kitchen-diner be?

Around 25 to 35 m² for the combined kitchen, dining and seating areas suits most family homes. Your survey shows what fits the house.

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 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.

Will I need a structural engineer?

Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.

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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