Ossett side extensions, designed and built
A side extension in Ossett 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 OssettFrom £20,500 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsWF5, WF12

When a side extension makes sense
- Detached and semi-detached houses with side land
- Houses where the rear garden is small
- Homes needing a utility, study or ground-floor bedroom
Planning and approvals in Ossett
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.
The planning position for a specific Ossett address depends on its history and any designations, which is why we check it at the first visit.
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).
Extensions in and around Ossett
Site visits are available across Ossett (WF5, WF12). We also work in nearby Dewsbury (2 miles), Batley (3 miles), Wakefield (3 miles), Morley (4 miles).
For homes towards South Yorkshire, Darton is around 7 miles away. Homes across Yorkshire and the Humber range from back-to-back and through terraces to large suburban semis, and extension options vary with them.
How much does a side extension cost in Ossett?
For Ossett we adjust our national guide rates by ×0.94, the factor we use for Yorkshire and the Humber. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Ossett: £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 |
For a figure based on your own dimensions, use our guide-price tool.
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
We visit your Ossett home, measure up, talk through what you want and check the planning position.
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
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Side extension questions answered
How long does a side extension take to build in Ossett?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Ossett, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in Ossett be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Can I build over my driveway?
Yes, if the foundations work and you keep any parking the council requires. Drains and services under drives are common, so we check before design.
How much does a side extension cost?
Our guide range is about £1,640 to £3,200 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £34,500 to £45,000 in Ossett.
Book a free site visit in Ossett
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.