Dulwich, London
Areas · Southwark · South London
Dulwich · SE1 · SE5 · SE15

House extensions in Dulwich

Dulwich sits in Southwark, where the streets are dominated by post-war and inter-war housing with straightforward foundations and fewer planning constraints. The build that pays back most reliably here is a full-width rear extension with a structural steel goalpost and sliding doors.

Typical all-in (inc VAT)
£109k–£169k
Build rate per m²
£2925–£4450
On-site programme
12–20 weeks

What we build in Dulwich

Most Dulwich projects we scope fall into three buckets: a side-return or rear infill that fixes a dark galley kitchen, a full-width rear extension that opens the ground floor to the garden, and a rear-plus-loft package that adds a bedroom while the scaffold is already up. Victorian terraces (East Dulwich, Nunhead), Georgian terraces (Bermondsey), 1930s (Camberwell).

Side-returnRear extensionLoft

Extension costs in Dulwich

A mid-spec 25 m² extension in Dulwich typically lands between £109,000 and £169,000 all-in — that figure includes professional fees, planning and Building Control, party wall, a 12% contingency and VAT at 20%. Ex-VAT build rates run £2925–£4450 per m² depending on glazing, structural spans and kitchen spend.

ProjectSizeDulwich all-in
Side return infill15–20 m²£82k – £127k
Full-width rear20–30 m²£109k – £169k
Wraparound30–45 m²£158k – £245k
Double-storey rear40–60 m²£213k – £330k

Planning permission in Dulwich

Dulwich Estate's private scheme of management adds an extra layer alongside council planning — factor in additional design review time.

Before you assume permitted development applies to your street, check whether your street falls inside a conservation area or an Article 4 direction — both are common in Southwark and both remove PD rights for rear and side extensions. Our London planning guide walks through the tests in order.

Party wall and neighbours

Terraces: two party walls standard. Dulwich Estate consent is separate from Party Wall.

Serve notice at least two months before you break ground. Budget £1,200–£2,400 per adjoining owner if they dissent and appoint their own surveyor — see the Party Wall Act guide.

Access, logistics and site set-up

Tight on-street parking means bay suspensions and timed deliveries — your builder should price this, not absorb it.

Every quote we issue for Dulwich prices skip permits, parking suspensions, protection and welfare explicitly in the preliminaries — so the number you sign is the number you pay.

Value added in Dulwich

Buyers in this area consistently pay a premium for open-plan kitchen-diners with direct garden access.

Typical programme

  1. Weeks 0–4Measured survey, design and structural calcs
  2. Weeks 4–12Planning or lawful development certificate, party wall notices
  3. Weeks 12–16Tender, builder selection and contract signing
  4. Weeks 16–34On site: groundworks, shell, watertight, first and second fix
  5. Week 35Building Control sign-off, snagging and handover

Full detail in the London extension timeline guide.

Why homeowners in Dulwich use us

  • KYB-verified builders only
  • Live Southwark project experience
  • Itemised fixed-price specifications
  • Insurance, warranty and accreditation checks
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