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Buckinghamshire

Kitchen-diner rear extensions in Buckinghamshire

An open-plan kitchen, dining and family room that opens straight onto the garden. We design and build rear extensions across Buckinghamshire, from Milton Keynes and High Wycombe to Aylesbury, covering single-storey kitchen extensions, two-storey additions, side returns and wraparounds.

Open-plan kitchen-diner in a rear extension with navy units, an oak-topped island and a vaulted ceiling with roof windows

We usually keep the working kitchen where the old one was and put the dining table in the new space by the doors, which suits most Milton Keynes homes. Commuter semis and detached houses make up much of Buckinghamshire, and longer gardens make England's prior approval route for deeper rear extensions worth considering.

How much does a kitchen-diner rear extension cost in Buckinghamshire?

A kitchen-diner rear extension in Buckinghamshire is priced at £2,130–£3,470 per square metre including VAT as a guide, before kitchen fit-out and fees. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.

Kitchen-diner rear extension guide prices in Buckinghamshire
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£25,500–£41,500
4 m wide × 5 m deep (20 m²)£42,500–£69,500
4 m wide × 6 m deep (24 m²)£51,000–£83,500

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 in Buckinghamshire?

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.

Where in Buckinghamshire do we work?

FAQ

Questions people ask

Should the sink face the garden?

If the plan allows, an island sink or hob facing the glass is a common choice. It needs a floor-level drain run, which is easy to lay in a new slab.

Can I have underfloor heating?

Yes. Wet underfloor heating in the new screed is the usual choice, often with the old room's radiators kept or replaced.

Where does the cooker extraction go?

Through the new wall or roof, ducted to outside. Recirculating hoods are possible but less effective.

Do you cover all of Buckinghamshire?

We cover 13 towns and districts in Buckinghamshire, including Milton Keynes, High Wycombe and Aylesbury.

Who builds the extension?

Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.

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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