Hertford, Hertfordshire
Kitchen-diner rear extension in Hertford
An open-plan kitchen, dining and family room that opens straight onto the garden. We design, get the approvals for and build kitchen-diner rear extensions in Hertford and the surrounding area, with one contract from the first survey to building control sign-off.
Hertford sits in Hertfordshire, with postcode districts including SG13 and SG14. A kitchen-diner is often the reason people in Hertford 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 Hertford?
In Hertford, 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 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a kitchen-diner rear extension in Hertford?
Planning for a kitchen-diner rear extension in Hertford follows the English householder rules.
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. 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 Hertford like to extend?
Post-war semis and newer estates are typical of Hertford, 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 Hertford 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.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
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 Hertford
From Hertford, the nearest places we also cover are Ware (2.4 miles) and Hoddesdon (3.7 miles).
- Kitchen-diner rear extension in Ware
- Kitchen-diner rear extension in Hoddesdon
- Kitchen-diner rear extension in Broxbourne
- Kitchen-diner rear extension in Welwyn Garden City
- Kitchen-diner rear extension in Hatfield
Other work in Hertford:
FAQ
Kitchen-diner rear extension questions in Hertford
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 planning permission for a rear extension in Hertford?
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.
Where does the cooker extraction go?
Through the new wall or roof, ducted to outside. Recirculating hoods are possible but less effective.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Is the site visit in Hertford free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
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.