Annexe extensions for homes in Muswell Hill
Thinking about an annexe extension for your Muswell Hill home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in Muswell HillFrom £71,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsN2, N6, N8, N10, N11
Planning rules that apply in Muswell Hill
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.
The planning position for a specific Muswell Hill address depends on its history and any designations, which is why we check it at the first visit.
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).
Included in a typical project
- Separate or shared heating and hot water
- Design for accessibility: level thresholds, wider doors, walk-in shower
- Kitchenette, shower room and bedroom finish
- Fire separation and alarms to building regulations
- Planning application describing ancillary use
Accessibility is cheaper to design in than to retrofit. Level access, a 900 mm door width, a level-access shower and space to turn a wheelchair can all be planned into the footprint for little extra cost.
Local to Muswell Hill
Across N2, N6, N8, N10, N11, N22, we can visit, measure and advise. Neighbouring towns we cover include Wood Green (1 mile), Friern Barnet (2 miles), Harringay (2 miles), Palmers Green (2 miles).
For homes towards Hertfordshire, Potters Bar is around 7 miles away. 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.
Guide prices for Muswell Hill
Prices below are for Muswell Hill, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Muswell Hill: £2,600 to £4,940 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £71,500 – £89,500 | £78,000 – £97,500 | £97,500 – £123,500 |
| One-bedroom annexe 35 m² | £91,000 – £114,000 | £109,000 – £136,500 | £136,500 – £173,000 |
| Larger annexe 45 m² | £117,000 – £146,500 | £140,000 – £175,500 | £175,500 – £222,500 |
For a figure based on your own dimensions, use our guide-price tool.
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
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Your questions about an annexe extension in Muswell Hill
Do you cover all of Muswell Hill?
Yes. We cover Muswell Hill and the surrounding parts of Greater London. Site visits are free and there is no obligation.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Muswell Hill, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Who do I contract with for an annexe extension in Muswell Hill?
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 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.
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).
Book a free site visit in Muswell Hill
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.