Single-storey rear extensions across Rawtenstall
From the first sketch to final sign-off, we plan and build single-storey extensions in Rawtenstall and the surrounding Lancashire area.
- Guide price in RawtenstallFrom £19,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsBB4

Single-storey extension prices in Rawtenstall
Labour and material costs vary across the UK, so for Rawtenstall we use our North West England factor (×0.95). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Rawtenstall: £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.
Do I need planning permission in Rawtenstall?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
Local to Rawtenstall
Postcode districts we cover around Rawtenstall include BB4. The same team covers Accrington (5 miles), Burnley (7 miles), Darwen (7 miles), Blackburn (9 miles), all within easy reach.
Bury, in Greater Manchester, is roughly 7 miles from Rawtenstall and also on our list. The North West has a high share of Victorian and Edwardian terraces with rear yards and outriggers, plus large areas of inter-war semis in the suburbs.
Included in a typical project
- Flat or pitched roof, rooflights or lantern
- Doors, windows, insulation, plastering and first fix to finish
- Planning route checked and the right approval obtained
- Measured survey and design
Our process, step by step
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Single-storey extension questions answered
Do you cover all of Rawtenstall?
Yes. We cover Rawtenstall and the surrounding parts of Lancashire. Site visits are free and there is no obligation.
Do I need building regulations approval in Rawtenstall?
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 Rawtenstall?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
How much does a single-storey extension cost per square metre?
Our guide range is about £1,660 to £3,230 per m² including VAT, depending on specification. A standard-spec 4 m × 5 m room usually lands at £38,500 to £49,500 in Rawtenstall, plus design and council fees.
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.
Book a free site visit in Rawtenstall
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.