Coombe, London
Areas · Kingston upon Thames · South London
Coombe · KT1 · KT2 · KT3

House extensions in Coombe

Coombe sits in Kingston upon Thames, where the streets are dominated by converted period houses and maisonettes where structural and access sequencing matters. The build that pays back most reliably here is a rear extension paired with a loft dormer, done under one scaffold and one contract.

Typical all-in (inc VAT)
£106k–£161k
Build rate per m²
£2800–£4300
On-site programme
12–20 weeks

What we build in Coombe

Most Coombe 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. Edwardian and 1930s semis, some Victorian villas in Surbiton and Coombe.

WraparoundDouble-storey rearLoft

Extension costs in Coombe

A mid-spec 25 m² extension in Coombe typically lands between £106,000 and £161,000 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 £2800–£4300 per m² depending on glazing, structural spans and kitchen spend.

ProjectSizeCoombe all-in
Side return infill15–20 m²£80k – £121k
Full-width rear20–30 m²£106k – £161k
Wraparound30–45 m²£154k – £233k
Double-storey rear40–60 m²£207k – £314k

Planning permission in Coombe

Kingston is one of the more design-conscious outer boroughs. Surbiton and Coombe conservation areas add scrutiny.

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 Kingston upon Thames and both remove PD rights for rear and side extensions. Our London planning guide walks through the tests in order.

Party wall and neighbours

Mostly semi-detached — one party wall neighbour.

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

Rear access via a side alley or garden gate speeds up muck-away and cuts labour cost noticeably.

Every quote we issue for Coombe 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 Coombe

Well-executed extensions here tend to return a healthy share of their cost at resale, particularly where they add a genuine third or fourth bedroom.

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 Coombe use us

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