Single-storey rear extensions for homes in Mirfield
We design and build single-storey extensions for houses in Mirfield, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in MirfieldFrom £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 districtsWF14
Included in a typical project
- Planning route checked and the right approval obtained
- Measured survey and design
- Building regulations drawings and structural calculations
- Foundations, drainage and groundworks
Covering Mirfield
Across WF14, we can visit, measure and advise. The same team covers Liversedge (2 miles), Heckmondwike (2 miles), Dewsbury (3 miles), Batley (3 miles), all within easy reach.
Homes across Yorkshire and the Humber range from back-to-back and through terraces to large suburban semis, and extension options vary with them.
Guide prices for Mirfield
Prices below are for Mirfield, using the Yorkshire and the Humber factor of ×0.94. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Mirfield: £1,640 to £3,200 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £19,500 – £23,500 | £23,000 – £29,500 | £29,000 – £38,500 |
| 4 m × 5 m 20 m² | £32,500 – £39,000 | £38,500 – £49,000 | £48,500 – £64,000 |
| 5 m × 6 m 30 m² | £49,000 – £58,000 | £57,500 – £73,500 | £73,000 – £96,000 |
For a figure based on your own dimensions, use our guide-price tool.
Planning rules that apply in Mirfield
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
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).
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
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
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Your questions about a single-storey extension in Mirfield
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Mirfield, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a single-storey extension take to build in Mirfield?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Do you cover all of Mirfield?
Yes. We cover Mirfield and the surrounding parts of West Yorkshire. Site visits are free and there is no obligation.
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.
How deep can a single-storey rear extension be without planning permission?
In England, up to 3 m beyond the original rear wall on a semi-detached or terraced house and 4 m on a detached house, within height and boundary limits. Through the larger home extension prior approval scheme those depths rise to 6 m and 8 m. Wales, Scotland and Northern Ireland use their own rules, which we check for your address.
Book a free site visit in Mirfield
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.