Home office extensions for homes in Friern Barnet
We design and build home office extensions for houses in Friern Barnet, with a written price once the survey and design are done and one point of contact throughout.
- Guide price in Friern BarnetFrom £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 districtsN2, N3, N10, N11, N12
How much does a home office extension cost in Friern Barnet?
Labour and material costs vary across the UK, so for Friern Barnet we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Friern Barnet: £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.
Do I need planning permission in Friern Barnet?
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).
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
Local to Friern Barnet
Postcode districts we cover around Friern Barnet include N2, N3, N10, N11, N12, N20. The same team covers Muswell Hill (2 miles), Finchley (2 miles), Wood Green (2 miles), Palmers Green (2 miles), all within easy reach.
Potters Bar, in Hertfordshire, is roughly 6 miles from Friern Barnet and also on our list. In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.
How the project works
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 Friern Barnet 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
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.
Home office extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Friern Barnet, 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 Friern Barnet?
On site, typically 8 to 12 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
Who do I contract with for a home office extension in Friern Barnet?
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.
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 Friern Barnet.
Book a free site visit in Friern Barnet
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.