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Berkhamsted, Hertfordshire

Kitchen-diner rear extension in Berkhamsted

For homes in Berkhamsted, 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.

We cover Berkhamsted (HP4) as part of our Hertfordshire work. A kitchen-diner is often the reason people in Berkhamsted extend: the back kitchen in post-war semis and newer estates 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 Berkhamsted?

For Berkhamsted we work from the East of England rate: £2,010–£3,290 per square metre of new floor, including VAT, standard specification. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.

Kitchen-diner rear extension prices in Berkhamsted
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

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 Berkhamsted?

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

Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is 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 Berkhamsted like to extend?

Post-war semis and newer estates are typical of Berkhamsted, 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 kitchen-diner rear extension in Berkhamsted 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 Berkhamsted

We also build kitchen-diner rear extensions in nearby Chesham (4.4 miles) and Tring (4.6 miles).

Other work in Berkhamsted:

All rear extensions in Berkhamsted

FAQ

Kitchen-diner rear extension questions in Berkhamsted

What postcode areas do you cover around Berkhamsted?

Including HP4, and the surrounding Hertfordshire area.

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

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

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.

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.

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.

Do you handle building control in Berkhamsted?

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

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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