Annexe extensions in Eastbourne: design, approvals and build
Eastbourne homeowners can use us for the whole annexe extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in EastbourneFrom £61,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsBN20, BN21, BN22, BN23, BN24
Guide prices for Eastbourne
For Eastbourne we adjust our national guide rates by ×1.12, the factor we use for South East England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Eastbourne: £2,240 to £4,260 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £61,500 – £77,500 | £67,000 – £84,500 | £84,000 – £106,500 |
| One-bedroom annexe 35 m² | £78,000 – £98,500 | £94,000 – £118,000 | £117,500 – £149,000 |
| Larger annexe 45 m² | £100,500 – £126,500 | £120,500 – £151,500 | £151,000 – £192,000 |
For a figure based on your own dimensions, use our guide-price tool.
Extensions in and around Eastbourne
Site visits are available across Eastbourne (BN20, BN21, BN22, BN23, BN24, BN26). Neighbouring towns we cover include Hailsham (7 miles), Seaford (8 miles), Bexhill-on-Sea (10 miles), Peacehaven (13 miles).
Just over the West Sussex border, Burgess Hill is about 22 miles away. In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
Planning and approvals in Eastbourne
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 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).
When an annexe extension makes sense
- Homes with a large side or rear garden
- Multi-generational families
- Relatives who need support close by
From first visit to completion
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions people ask about annexe extensions
How long does an annexe extension take to build in Eastbourne?
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 Eastbourne, 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 I need building regulations approval in Eastbourne?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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).
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 Eastbourne
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.