Annexe extensions in York: design, approvals and build
From the first sketch to final sign-off, we plan and build annexe extensions in York and the surrounding North Yorkshire area.
- Guide price in YorkFrom £51,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsYO1, YO10, YO23, YO24, YO30
Annexe extension prices in York
Labour and material costs vary across the UK, so for York we use our Yorkshire and the Humber factor (×0.94). The ranges include VAT and exclude design, structural and council fees.
Typical rates in York: £1,880 to £3,570 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £51,500 – £65,000 | £56,000 – £70,500 | £70,500 – £89,500 |
| One-bedroom annexe 35 m² | £65,500 – £82,500 | £78,500 – £99,000 | £98,500 – £125,500 |
| Larger annexe 45 m² | £84,500 – £106,000 | £101,500 – £127,000 | £126,500 – £161,000 |
Try the guide-price tool to see a range for your own size and finish.
Extensions in and around York
We cover York and the postcode districts YO1, YO10, YO23, YO24, YO30, YO31. Neighbouring towns we cover include Selby (12 miles), Harrogate (19 miles), Ripon (24 miles), Northallerton (31 miles).
Just over the East Riding of Yorkshire border, Goole is about 19 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.
When an annexe extension makes sense
- Relatives who need support close by
- Multi-generational families
- Homes with a large side or rear garden
Accessibility is cheaper to design in than to retrofit. Level access, a 900 mm door width, a level-access shower and space to turn a wheelchair can all be planned into the footprint for little extra cost.
Do I need planning permission in York?
In England an annexe that stays part of the household and connects to the house is assessed as an extension, but its size usually takes it beyond permitted development, so a householder application describing the ancillary use is the normal route.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
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
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Annexe extension questions answered
How long does an annexe extension take to build in York?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 10–16 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for York, 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 you cover all of York?
Yes. We cover York and the surrounding parts of North Yorkshire. Site visits are free and there is no obligation.
How much does an annexe extension cost?
Our guide range is about £1,880 to £3,570 per m² including VAT. A one-bedroom annexe of about 35 m² is typically £78,500 to £99,000 at standard spec in York.
Will an annexe affect council tax?
It can. Some annexes are assessed separately for council tax, with discounts or exemptions in some cases when occupied by a relative. Check with the Valuation Office Agency (England and Wales), your local assessor (Scotland) or Land & Property Services (Northern Ireland).
Book a free site visit in York
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.