Annexe extensions in Whitby
Thinking about an annexe extension for your Whitby home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in WhitbyFrom £51,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsYO21
Planning and approvals in Whitby
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Who an annexe extension suits
- Relatives who need support close by
- Multi-generational families
- Homes with a large side or rear garden
Covering Whitby
Postcode districts we cover around Whitby include YO21. Nearby, we also take on projects in Redcar (17 miles), Scarborough (18 miles), Middlesbrough (22 miles), Northallerton (33 miles).
Homes across Yorkshire and the Humber range from back-to-back and through terraces to large suburban semis, and extension options vary with them.
What should I budget for an annexe extension in Whitby?
For Whitby 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 Whitby: £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.
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
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Questions people ask about annexe extensions
How long does an annexe extension take to build in Whitby?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 10–16 weeks design and approvals.
Will my neighbours in Whitby 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 see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Whitby, 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 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 Whitby.
Can the annexe have its own front door?
Yes, many do, but it should still connect to the main house to stay clearly part of it.
Book a free site visit in Whitby
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.