Weymouth, Dorset
Kitchen-diner rear extension in Weymouth
For homes in Weymouth, 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 Weymouth (DT3 and DT4) as part of our Dorset work. 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 Weymouth homes.
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 Weymouth?
For Weymouth we work from the South West England rate: £1,980–£3,220 per square metre of new floor, including VAT, standard specification. South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £23,500–£38,500 |
| 4 m wide × 5 m deep (20 m²) | £39,500–£64,500 |
| 4 m wide × 6 m deep (24 m²) | £47,500–£77,500 |
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 Weymouth?
The planning route for a kitchen-diner rear extension in Weymouth is set by England's householder rules and your council.
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 Weymouth like to extend?
Stone-built and rendered houses are common around Weymouth, so matching the walling is a design decision in its own right: natural stone, reconstituted stone or a render finish across old and new.
How a kitchen-diner rear extension in Weymouth comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
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 Weymouth
From Weymouth, the nearest places we also cover are Portland (3.3 miles) and Dorchester (7.2 miles).
- Kitchen-diner rear extension in Portland
- Kitchen-diner rear extension in Dorchester
- Kitchen-diner rear extension in Bridport
- Kitchen-diner rear extension in Blandford Forum
- Kitchen-diner rear extension in Poole
Other work in Weymouth:
FAQ
Kitchen-diner rear extension questions in Weymouth
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 Weymouth?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
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.
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.
Do I need planning permission for a rear extension in Weymouth?
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.
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.