Home office extensions in Lancing
A home office extension in Lancing 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 LancingFrom £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 districtsBN15

Planning and approvals in Lancing
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
Covering Lancing
Across BN15, we can visit, measure and advise. Neighbouring towns we cover include Shoreham-by-Sea (2 miles), Worthing (2 miles), Littlehampton (10 miles), Burgess Hill (12 miles).
Just over the East Sussex border, Portslade is about 5 miles away. The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
Is a home office extension right for your house?
- Households that need a second quiet room
- Homes where a loft or garden room is not practical
- People who work from home most of the week
How much does a home office extension cost in Lancing?
For Lancing 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 Lancing: £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 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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions people ask about home office extensions
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Lancing, 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 Lancing?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Will my neighbours in Lancing 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 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 Lancing.
Book a free site visit in Lancing
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.