Broxbourne, Hertfordshire
Single-storey rear extension in Broxbourne
Single-storey rear extension in Broxbourne: ground-floor space across the back of the house, usually for a kitchen, dining or family room. We measure the house, show you what the rules allow, price it in writing and build it.
Broxbourne is covered from our Hertfordshire round, including EN7, EN8 and EN10. A depth of 3 to 4 metres keeps many single-storey rear extensions in Broxbourne within permitted development, subject to the house's planning history.
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 single-storey rear extension cost in Broxbourne?
For Broxbourne 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.
| 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 single-storey rear extension in Broxbourne?
Here is how the rules in England apply to a single-storey rear extension in Broxbourne.
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. 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 Broxbourne like to extend?
Post-war semis and newer estates are typical of Broxbourne, 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 single-storey rear extension in Broxbourne comes together
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.
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.
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.
Single-storey rear extensions near Broxbourne
From Broxbourne, the nearest places we also cover are Hoddesdon (1.0 miles) and Cheshunt (3.3 miles).
- Single-storey rear extension in Hoddesdon
- Single-storey rear extension in Cheshunt
- Single-storey rear extension in Waltham Abbey
- Single-storey rear extension in Hertford
- Single-storey rear extension in Waltham Cross
Other work in Broxbourne:
FAQ
Single-storey rear extension questions in Broxbourne
Can you match the brick or stone on my Broxbourne house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
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 a structural engineer?
Yes for the beam over the new opening and usually for the foundations. Their calculations go to building control with the drawings.
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.
What postcode areas do you cover around Broxbourne?
Including EN7, EN8 and EN10, and the surrounding Hertfordshire area.
Is the site visit in Broxbourne free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.