Single-storey rear extensions for homes in Derbyshire
Our design and build teams take on single-storey extensions in Derbyshire, from the first measured survey through planning and building control to the finished room.
- Guide priceFrom £19,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Towns covered12
- Site visitFree, no obligation

Towns in Derbyshire
Local to Derbyshire
Towns we cover in Derbyshire include Derby, Chesterfield, Long Eaton, Ilkeston, Swadlincote, Staveley, Belper, Heanor. The East Midlands has plenty of inter-war and post-war semis and detached houses with room to extend, alongside Victorian terraces in the towns.
Do I need planning permission in Derbyshire?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Included in a typical project
- Foundations, drainage and groundworks
- Doors, windows, insulation, plastering and first fix to finish
- Planning route checked and the right approval obtained
- Walls, steel beams and the new opening into the house
What should I budget for a single-storey extension in Derbyshire?
These guide figures apply our East Midlands adjustment (×0.95) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Derbyshire: £1,660 to £3,230 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £19,500 – £23,500 | £23,000 – £30,000 | £29,500 – £39,000 |
| 4 m × 5 m 20 m² | £33,000 – £39,000 | £38,500 – £49,500 | £49,000 – £65,000 |
| 5 m × 6 m 30 m² | £49,500 – £58,500 | £58,000 – £74,500 | £74,000 – £97,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions people ask about single-storey extensions
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Derbyshire, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in Derbyshire?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a single-storey extension take to build in Derbyshire?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Flat roof or pitched roof?
Flat roofs give more headroom inside and suit lanterns and rooflights; pitched roofs can blend better with older houses. Both meet building regulations when built properly. See our flat roof and pitched roof pages for the details.
Can I stay in the house during the build?
Usually yes. Most of the work happens outside until the final weeks, when we open the rear wall. We plan that stage carefully and seal the opening with a temporary screen to keep dust down.
Book a free site visit in Derbyshire
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.