Greenwich, London
Boroughs · South London
Greenwich · Outer London

House extensions in Greenwich

Greenwich covers everything from UNESCO-controlled Georgian streets to permissive Eltham semis. Cost and planning complexity vary enormously by postcode.

Typical all-in (inc VAT)
£100k–£155k
Cost vs London base
On par
Postcodes covered
SE3 · SE7 · SE9 · SE10

Housing stock in Greenwich

Georgian terraces (Greenwich), 1930s semis (Eltham), post-war and new-build (Kidbrooke).

Rear dormerHip-to-gableMansard loft

Planning in Greenwich

Greenwich West is a UNESCO World Heritage buffer — design controls are very tight. Elsewhere the borough is fairly permissive.

Party Wall Act — what to expect

Semi-detached prevalent in Eltham; typically one party wall.

Read the Party Wall etc. Act 1996 guide for full detail on notices, timelines and surveyor costs.

Typical costs in Greenwich

For a mid-spec 25 m² rear dormer loft conversion, all-in (structural design, building control, party wall, VAT and 12% contingency), expect roughly £100,000 to £155,000. A mansard, a hip-to-gable with high-spec en-suite joinery or a conservation-area application will push above the top of this range; a self-built rooflight conversion comes in well under the bottom.

Cost tier
Outer London · Baseline vs London average

Our calculator applies a 1.00× multiplier automatically for Greenwich projects. Get an itemised breakdown in 60 seconds.

Get your Greenwich estimate

Areas we cover in Greenwich

SE3SE7SE9SE10SE18

Why homeowners in Greenwich pick us

  • KYB-verified builders only
  • Local Greenwich project experience
  • Fixed, itemised written quotes
  • Full insurance & warranty checks
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