House extension cost
in Brook Green.
Brook Green — the village-feel pocket of W6 around the namesake park. Sandwiched between Hammersmith and Kensington, the streets here hold some of west London's most coveted Victorian housing.
What makes extension work in Brook Green distinct.
Housing: Mid-Victorian three-storey terraces with classical detailing, plus a handful of detached villas on the green itself.
Planning: Brook Green Conservation Area covers most of W6 north of Shepherd's Bush Road. Full planning is the rule, not the exception.
Applications go to LB Hammersmith & Fulham. We submit on your behalf and handle party wall awards, build-over agreements and conservation officer correspondence end-to-end.
The five extension types — W6 numbers.
All figures inclusive of design, planning, build, contingency and VAT. The Brook Green multiplier (1.10×) 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 Brook Green and beyond.
Send me the guide.
What Brook Green homeowners ask us.
How much does a house extension cost in Brook Green in 2026?
Typical 2026 Brook Green ranges (inc. design, planning, build, contingency & VAT): side-return extensions £99k–£176k; single-storey rear £121k–£231k; wraparound £187k–£352k; double-storey rear £198k–£418k; basement £275k–£825k. The Brook Green multiplier (1.10×) reflects local labour rates, scaffold logistics and finish expectations.
Do I need planning permission for an extension in Brook Green?
Brook Green Conservation Area covers most of W6 north of Shepherd's Bush Road. Full planning is the rule, not the exception. 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 LB Hammersmith & Fulham.
What extension type works best for Brook Green houses?
Mid-Victorian three-storey terraces with classical detailing, plus a handful of detached villas on the green itself. 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 Brook Green?
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. LB Hammersmith & Fulham processes planning applications in approximately 8–13 weeks depending on backlog.
What hidden costs catch Brook Green homeowners out on extensions?
In W6 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 Brook Green extensions?
Yes — Brook Green is within our core London catchment. Our studio is at 20 Dawes Road in Fulham, 2.0km from Brook Green. We've delivered extensions across the W6 postcode and our subcontractor network covers Hammersmith & Fulham. Free site visit, fixed-price quote, 10-year HomePro guarantee on the finished work.
Extension pricing for Brook Green’s neighbours.
Twenty minutes on site in Brook Green.
On us.
Nick Elias RIBA and Vladimir will visit your Brook Green 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 Brook Green extension using the same 2026 rate card we quote real clients with.
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