Hailsham home office extensions, designed and built
If you live in Hailsham and want more space without moving, a home office extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in HailshamFrom £17,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–12 weeks on site
- Postcode districtsBN27

Local to Hailsham
Site visits are available across Hailsham (BN27). We also work in nearby Eastbourne (7 miles), Seaford (9 miles), Bexhill-on-Sea (9 miles), Uckfield (10 miles).
Just over the West Sussex border, Burgess Hill is about 18 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.
Will the council need to approve it?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
What should I budget for a home office extension in Hailsham?
These guide figures apply our South East England adjustment (×1.12) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Hailsham: £2,070 to £3,810 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 3.2 m 8 m² | £17,500 – £21,500 | £19,000 – £24,500 | £24,000 – £30,500 |
| 3 m × 3.6 m 11 m² | £22,500 – £27,500 | £26,000 – £33,500 | £33,000 – £42,000 |
| 3 m × 5 m 15 m² | £31,000 – £37,000 | £36,000 – £45,500 | £45,000 – £57,500 |
For a figure based on your own dimensions, use our guide-price tool.
What we take care of
- Sound insulation to the adjoining rooms
- Layout for desk, storage and video calls
- Heating or cooling sized for the room
- Window and rooflight placement to avoid screen glare
- Data cabling and plenty of sockets
What happens next
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 Hailsham home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Home office extension questions answered
Will my neighbours in Hailsham 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.
Do you cover all of Hailsham?
Yes. We cover Hailsham and the surrounding parts of East Sussex. Site visits are free and there is no obligation.
Do I need building regulations approval in Hailsham?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I claim the cost against tax?
Building work on your home is not normally an allowable business expense, and claiming it can have capital gains tax effects. Speak to an accountant before assuming any tax relief.
How much does a home office extension cost?
Our guide range is about £2,070 to £3,810 per m² including VAT. An 11 m² standard-spec office is typically £26,000 to £33,500 in Hailsham.
Book a free site visit in Hailsham
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.