Stevenage, Hertfordshire
Kitchen-diner rear extension in Stevenage
Thinking about a kitchen-diner rear extension in Stevenage? An open-plan kitchen, dining and family room that opens straight onto the garden. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Stevenage sits in Hertfordshire, with postcode districts including SG1 and SG2. A kitchen-diner is often the reason people in Stevenage 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 Stevenage?
In Stevenage, our guide for a kitchen-diner rear extension is £2,010–£3,290 per square metre including VAT for a standard specification. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.
| Size | Guide 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 Stevenage?
Here is how the rules in England apply to a kitchen-diner rear extension in Stevenage.
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.
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. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Stevenage like to extend?
Post-war semis and newer estates are typical of Stevenage, 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 Stevenage comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
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 Stevenage
We also build kitchen-diner rear extensions in nearby Codicote (3.9 miles) and Hitchin (4.8 miles).
- Kitchen-diner rear extension in Codicote
- Kitchen-diner rear extension in Hitchin
- Kitchen-diner rear extension in Letchworth Garden City
- Kitchen-diner rear extension in Baldock
- Kitchen-diner rear extension in Welwyn Garden City
Other work in Stevenage:
FAQ
Kitchen-diner rear extension questions in Stevenage
How long does a rear extension take to build in Stevenage?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.
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.
What postcode areas do you cover around Stevenage?
Including SG1 and SG2, and the surrounding Hertfordshire area.
Do you handle building control in Stevenage?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Do I need planning permission for a rear extension in Stevenage?
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.