Side extensions in Halifax
A side extension in Halifax starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in HalifaxFrom £20,500 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsHD6, HX1, HX2, HX3, HX4

Side extension prices in Halifax
These guide figures apply our Yorkshire and the Humber adjustment (×0.94) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Halifax: £1,640 to £3,200 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £20,500 – £25,000 | £23,000 – £30,000 | £29,000 – £38,500 |
| 3 m × 6 m 18 m² | £29,500 – £36,000 | £34,500 – £45,000 | £43,500 – £58,000 |
| 3 m × 8 m 24 m² | £39,000 – £47,500 | £46,000 – £60,000 | £58,500 – £77,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Planning and approvals in Halifax
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
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.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Included in a typical project
- Structure, roof tied into the house
- Survey, design and street-view drawings
- Planning route checked or application made
- Foundations near boundaries and any drains
- Windows, doors and finishes to match
- New openings through the side wall
Local to Halifax
Across HD6, HX1, HX2, HX3, HX4, HX5, we can visit, measure and advise. Neighbouring towns we cover include Brighouse (3 miles), Huddersfield (5 miles), Cleckheaton (6 miles), Liversedge (6 miles).
Just over the Greater Manchester border, Saddleworth is about 13 miles away. Yorkshire and the Humber combines stone-built terraces in the Pennine towns with brick semis and newer estates elsewhere, so materials and roof details need matching with care.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Halifax
Do you cover all of Halifax?
Yes. We cover Halifax and the surrounding parts of West Yorkshire. Site visits are free and there is no obligation.
Do I need building regulations approval in Halifax?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Halifax, 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 close to the boundary can I build?
It depends on height. In England, within 2 m of a boundary the eaves must not exceed 3 m under permitted development. Building on the boundary is possible but brings party wall and maintenance access issues we plan for.
Can I build a side extension without planning permission?
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a planning application.
Book a free site visit in Halifax
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.