Home office extensions in Mitcham
A home office extension in Mitcham 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 MitchamFrom £20,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–12 weeks on site
- Postcode districtsCR4, SM4, SM5, SW16, SW17

Covering Mitcham
Across CR4, SM4, SM5, SW16, SW17, SW19, we can visit, measure and advise. The same team covers Morden (1 mile), Tooting (2 miles), Wimbledon (2 miles), Streatham (2 miles), all within easy reach.
Ewell, in Surrey, is roughly 5 miles from Mitcham and also on our list. Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
How much does a home office extension cost in Mitcham?
Labour and material costs vary across the UK, so for Mitcham we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Mitcham: £2,400 to £4,420 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 3.2 m 8 m² | £20,500 – £25,000 | £22,000 – £28,500 | £28,000 – £35,500 |
| 3 m × 3.6 m 11 m² | £26,000 – £31,500 | £30,500 – £39,000 | £38,500 – £49,000 |
| 3 m × 5 m 15 m² | £36,000 – £43,000 | £41,500 – £53,000 | £52,500 – £66,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
What we take care of
- Data cabling and plenty of sockets
- Sound insulation to the adjoining rooms
- Heating or cooling sized for the room
- Window and rooflight placement to avoid screen glare
- Layout for desk, storage and video calls
Do I need planning permission in Mitcham?
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.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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).
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
We visit your Mitcham 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
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Mitcham
Who do I contract with for a home office extension in Mitcham?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Mitcham, 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 long does a home office extension take to build in Mitcham?
On site, typically 8 to 12 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
Is an attached office better than a garden office?
An attached office shares the house heating and broadband, adds floor area to the home, and needs no garden path in the rain. A garden building can be cheaper and quicker but is a separate structure.
How much does a home office extension cost?
Our guide range is about £2,400 to £4,420 per m² including VAT. An 11 m² standard-spec office is typically £30,500 to £39,000 in Mitcham.
Book a free site visit in Mitcham
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.