QUICK ANSWER: A house extension in Fulham typically costs £2,500 to £4,500 per square metre in 2026. A side return extension runs roughly £65,000–£110,000, a single-storey rear extension £70,000–£150,000, and a wraparound extension £110,000–£220,000, all figures including design, planning, and build. Fulham has multiple conservation areas — Hurlingham, Parsons Green, Walham Green, Moore Park, Sands End among them — and a borough-wide Article 4 Direction means basement work always requires planning permission, regardless of location within SW6.
Most companies writing about Fulham extension costs have never actually stood on a Fulham street. We have — our office is on Fulham Palace Road, which means when we quote a side return on Munster Road or a rear extension near Parsons Green, it's based on having walked past the property, not a spreadsheet built from a national average. Here's what an extension genuinely costs in SW6 in 2026, from people who can see the postcode from their own front door.
Fulham's Housing Stock and Why Location Within SW6 Matters
Fulham is dominated by Victorian terraces, many built on clay subsoil that affects foundation design more than homeowners expect — a genuine local factor that a builder working from outside the area can easily underprice. Streets like Hurlingham Road, Broomhouse Lane, and Munster Road each carry slightly different party wall and access considerations, and several fall within conservation areas — Hurlingham, Parsons Green, Walham Green, Moore Park, and Sands End cover a meaningful share of the borough.
Fulham sits within the London Borough of Hammersmith & Fulham, entirely separate from Wandsworth (which covers Battersea and Putney) — worth knowing, since the two boroughs apply different planning standards and a builder unfamiliar with LBHF specifically can misjudge what's achievable. A householder planning application to LBHF costs £258 in 2026. The borough's Article 4 Direction means basement excavation always requires full planning permission here, with no permitted development route available regardless of address.
What a House Extension Actually Costs in Fulham
Extension typeTypical 2026 cost (all-in)
Side return extension
£65,000 – £110,000
Single-storey rear extension
£70,000 – £150,000
Wraparound extension
£110,000 – £220,000
Double-storey rear extension
£130,000 – £230,000
Loft conversion (rear dormer)
£55,000 – £85,000
A well-executed wraparound extension on a Fulham Victorian terrace typically adds £150,000–£280,000 to a property's value — a genuinely strong return, which is part of why side return and wraparound schemes remain the most requested project type across SW6. These figures include design, planning, and build cost — not just the build cost some online estimators quote in isolation, which is how a headline figure can look meaningfully lower than what actually lands on a final invoice.
With the average local home now selling for around £1.2 million, a whole-house renovation is a significant enough investment that getting the planning picture right from day one genuinely matters.
Renovation scopeTypical 2026 cost (all-in)
Kitchen only
£24,000 – £76,000
Bathroom only
£14,000 – £47,000
Single room refurbishment
£18,000 – £56,000
Whole house renovation
£170,000 – £420,000
Period restoration (listed or heavily original)
£235,000 – £850,000
Conservation area specification requirements — matched brickwork, appropriate window proportions, sympathetic materials — typically add 10–20% to build costs versus an equivalent project outside a conservation boundary, which is worth budgeting for from the outset rather than discovering at quote stage.
Frequently Asked Questions
Do I need planning permission for a side return extension in Fulham? Usually yes. Side return extensions typically exceed permitted development limits because the side element isn't covered by the same allowances as a straightforward rear extension, so a full planning application to Hammersmith & Fulham is the standard route for most SW6 side returns.
Is Fulham more expensive to build in than nearby areas? Generally yes, reflecting local labour rates, conservation area material requirements, and the specification level expected on Fulham's Victorian terrace stock — costs typically sit toward the upper end of West London ranges.
How long does planning permission take in Hammersmith & Fulham? A standard householder application has a statutory target of 8 weeks, though conservation area applications and anything requiring a heritage or design statement often take longer in practice.
Get a Quote From Down the Road
Dominant Construction has been based on Fulham Palace Road for over 15 years, delivering extensions, renovations, and loft conversions across SW6 and the wider West London area — FMB-registered, working to JCT contracts, with a fixed price agreed after an actual site visit, not a form filled in online.
Call 020 7118 6155, walk in and see us at 185 Fulham Palace Road, W6 8QX, or see recent projects at dominantconstruction.co.uk.