Loft conversion cost London/Clapham
SW4 · Lambeth · 2026 prices

Loft conversion cost
in Clapham.

Clapham — SW4 — south-east of Battersea, centred on the common. A mix of Victorian terraces, Georgian houses around the common, and pockets of inter-war housing.

£43k–£211k
typical Clapham range
SW4
Lambeth
5.0 km
from our Fulham studio
12-month
Workmanship warranty on second-fix fittings, signed by the trades
Clapham housing stock & planning

What makes loft work in Clapham distinct.

Housing: Two- and three-storey Victorian terraces, Georgian houses on the common itself, and 1920s/30s housing on the southern edges.

Planning: Clapham Common conservation areas (multiple) cover the common itself and adjoining streets. Most of central Clapham retains PD rights.

Applications go to LB Lambeth. We submit on your behalf and handle conservation officer correspondence end-to-end.

Streets we work in Clapham
Abbeville RoadOld TownCavendish RoadClapham High StreetNelson's Row
Loft prices for Clapham, by type

The five loft types — SW4 numbers.

All figures inclusive of design, planning, build, contingency and VAT. The Clapham multiplier (0.96×) reflects local labour, scaffolding logistics, conservation requirements and finish expectations.

Velux / rooflight only
Clapham typical
£43k£72k
Roof stays as-is. Cheapest route, limited headroom, almost always PD.
Rear dormer
Clapham typical
£72k£115k
The London classic. Full standing height across most of the floor.
L-shape dormer
Clapham typical
£91k£144k
Dormer + side return at loft level. Master + en-suite typical.
Hip-to-gable + rear dormer
Clapham typical
£106k£163k
Semi-detached / end-of-terrace. Maximum floor area gain.
Mansard
Clapham typical
£125k£211k
Rear roof replaced. Premium choice for period houses. Full planning.
Run my Clapham calculator →Read the full London loft guide
Free download · 24 pages

The 2026 London Loft Cost Guide.

Borough-by-borough pricing, a full cost breakdown, PD vs full planning explained, and the seven hidden costs to watch for in Clapham and beyond.

Already 600+ London homeowners on the list.
Instant access

Send me the guide.

Clapham loft FAQ

What Clapham homeowners ask us.

Do I need planning permission for a loft in Clapham?

Clapham Common conservation areas (multiple) cover the common itself and adjoining streets. Most of central Clapham retains PD rights. Outside conservation areas, most rear-dormer conversions in Clapham qualify for permitted development (PD) within the 40m³ (terrace) or 50m³ (semi/detached) volume limits. Mansards always need full planning. We check your specific address before quoting and submit the application on your behalf.

How does Lambeth Council approach loft conversions in Clapham?

Generally pragmatic — LB Lambeth has clear policy on rear dormers and Lawful Development Certificates are usually issued in 8 weeks for PD-compliant submissions. Conservation-area applications need more design care but pass at typical rates when the dormer is recessed and materials match.

How long does a Clapham loft conversion take?

Typical timeline: 6–10 weeks for design and planning (longer in conservation areas like much of Clapham), then 8–14 weeks on site for a standard dormer, 12–18 weeks for an L-shape or hip-to-gable, and 14–20 weeks for a mansard. LB Lambeth processes PD-route Lawful Development Certificates in approximately 8 weeks.

What does a loft conversion add to Clapham property values?

In SW4, a well-executed loft conversion typically adds 15–25% to property value — often more in prime postcodes. The ROI is strongest when you add a double bedroom plus en-suite, which is the standard L-shape dormer configuration. Property uplift on a £43k–£211k build commonly exceeds the build cost by 30–60%.

Does 2VP work on Clapham loft conversions?

Yes — Clapham is within our core London catchment. Our studio is at 20 Dawes Road in Fulham, 5.0km from Clapham. We've delivered loft conversions across the SW4 postcode and our subcontractor network covers Lambeth. Free site visit, itemised quotation, 12-month workmanship warranty on second-fix fittings on the finished work — with an optional 10-year HomePro guarantee on request, arranged with HomePro and paid directly to them at 2.5% of the contract value.

Nicholas Elias RIBA
Vladimir Castravet
Free site visit · Clapham

Twenty minutes on site in Clapham.
On us.

Nick Elias RIBA and Vladimir will visit your Clapham home, walk the loft, check head height, advise on PD vs planning, and give you a realistic budget and programme — even if a loft isn’t right for your house.

Ready to build in Clapham?
See our loft conversion work in Clapham.
View Clapham projects →

One number. Sixty seconds. No callback.

Price your Clapham loft conversion using the same 2026 rate card we quote real clients with.

Price my Clapham loft →
If this is your project

The home you actually want, finished on the date in the contract — and you watch every day of it happen from your phone.

How fast
  • Your number in 60 seconds
  • Itemised stage breakdown in 2 minutes
  • Survey within 7 days
What you do

You answer 3 questions. We do the drawings, planning, party wall, trades and snagging.

What protects you
  • 10% to mobilise, then weekly against work already done — with 5% held past handover: 2.5% released at practical completion and 2.5% at the end of the 12-month defects period
  • £550 survey fee credited in full against your contract
  • Every variation priced and signed before a penny is spent

The date is a term of the contract. We finish on the agreed date, or we pay you £500 for every week we are late.

Do not take our word for it

4.8 from 16 Google reviews

Every review is published in full on our reviews page, including the one-star. Google is the only platform we quote a rating for, because it is the only one we can evidence.

★★★★★
As a structural engineer, I've collaborated with 2VP Projects Ltd on several residential projects in London. Their attention to detail, proactive site management, and clear communication make every stage—from design to execution—smooth and efficient. It's rare to find a contractor who values both precision and professionalism at this level. A truly reliable partner.
Igors Smirnovs · Structural engineer we have worked with · June 2025
★★★★★
Great company to work with. Professional, reliable and easy to deal with. Vladimir and the team are always responsive, straightforward and genuinely care about doing things properly. I've had a very positive experience working with 2VP and would happily recommend them.
Sheen Delicatessen · Business client · August 2026
★★★★★
Extension went smoothly from start to finish. Communication was great throughout, and the team delivered exactly what we asked for. Thank you, 2VP!
Dan Martea · August 2026
Warranties and protections

What is covered, and by whom

A builder’s own guarantee is worth exactly as much as the company standing behind it. Here is what comes as standard, what you can add, and what has to come from somebody other than us — set out in full on our insurance and guarantee page.

Included in the contract
  • 12-month workmanship warranty on second-fix fittings
  • £5M public liability
  • £10M employer's liability
  • £2M professional indemnity
Optional, on request
  • HomePro insurance-backed guarantee, 10 years
  • Priced at 2.5% of the contract sum
  • Underwritten by an insurer, so it survives us
Not from us
  • 10-year structural warranty on a new dwelling (NHBC / LABC / Premier)
  • Professional fees — architect, engineer, building control
  • We will tell you when you need one rather than let you find out