House extension cost
in West Brompton.
West Brompton — the cemetery-and-station hinge between Fulham, Chelsea and Earls Court. The streets between Lillie Road and the Old Brompton Road are dense Victorian terraces with strong loft potential.
What makes extension work in West Brompton distinct.
Housing: Three- and four-storey Victorian terraces, many converted to flats but a meaningful share still single-family.
Planning: The Earls Court and Brompton Cemetery conservation areas overlap parts of SW10; expect full planning on most loft applications.
Applications go to Royal Borough of Kensington & Chelsea. We submit on your behalf and handle party wall awards, build-over agreements and conservation officer correspondence end-to-end.
The five extension types — SW10 numbers.
All figures inclusive of design, planning, build, contingency and VAT. The West Brompton multiplier (1.12×) reflects local labour, scaffolding logistics, conservation requirements and finish expectations.
The 2026 London Extension Cost Guide.
Borough-by-borough pricing, a full £200k cost breakdown, PD vs full planning explained, and the seven hidden costs to watch for in West Brompton and beyond.
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What West Brompton homeowners ask us.
How much does a house extension cost in West Brompton in 2026?
Typical 2026 West Brompton ranges (inc. design, planning, build, contingency & VAT): side-return extensions £101k–£179k; single-storey rear £123k–£235k; wraparound £190k–£358k; double-storey rear £202k–£426k; basement £280k–£840k. The West Brompton multiplier (1.12×) reflects local labour rates, scaffold logistics and finish expectations.
Do I need planning permission for an extension in West Brompton?
The Earls Court and Brompton Cemetery conservation areas overlap parts of SW10; expect full planning on most loft applications. Outside conservation areas, single-storey rear extensions up to 3m (terrace/semi) or 4m (detached) usually qualify for permitted development. Side-returns, wraparounds, double-storey extensions and anything in a conservation area need full planning. Applications go to Royal Borough of Kensington & Chelsea.
What extension type works best for West Brompton houses?
Three- and four-storey Victorian terraces, many converted to flats but a meaningful share still single-family. On this housing stock, the most common 2VP extension is a single-storey rear or wraparound — adding 20–35 m² of open-plan kitchen-diner. Double-storey extensions become viable on properties with rear gardens deep enough to absorb the additional volume without overshadowing.
How long does an extension take in West Brompton?
Allow 8–12 weeks for design and planning (longer in conservation areas), then 16–22 weeks on site for a single-storey, 22–30 weeks for a wraparound or double-storey, and 28–40 weeks for a basement. Royal Borough of Kensington & Chelsea processes planning applications in approximately 8–13 weeks depending on backlog.
What hidden costs catch West Brompton homeowners out on extensions?
In SW10 the top items are: party wall awards (£1,000–£3,000 per neighbour — common on terraced streets), build-over agreements with Thames Water (£300–£1,500 where drains run beneath the proposed extension), conservation officer consultations, structural engineer fees, drainage and asbestos surveys, and VAT at 20% on top of the base build cost. All of these are itemised in our fixed-price quote.
Does 2VP work on West Brompton extensions?
Yes — West Brompton is within our core London catchment. Our studio is at 20 Dawes Road in Fulham, 1.4km from West Brompton. We've delivered extensions across the SW10 postcode and our subcontractor network covers Kensington & Chelsea. Free site visit, fixed-price quote, 10-year HomePro guarantee on the finished work.
Extension pricing for West Brompton’s neighbours.
Twenty minutes on site in West Brompton.
On us.
Nick Elias RIBA and Vladimir will visit your West Brompton home, walk the site, check planning constraints, advise on PD vs full planning, and give you a realistic budget and programme — even if an extension isn’t the right move.
One number. Sixty seconds. No callback.
Price your West Brompton extension using the same 2026 rate card we quote real clients with.
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