Waltham Forest, London
Boroughs · East London
Waltham Forest · Inner London

House extensions in Waltham Forest

Walthamstow's E17 terraces are the borough's bread and butter — well-precedented rear dormers and hip-to-gable conversions with strong post-project value uplift.

Typical all-in (inc VAT)
£105k–£160k
Cost vs London base
+2%
Postcodes covered
E4 · E10 · E11 · E17

Housing stock in Waltham Forest

Victorian terraces (Walthamstow Village), Edwardian bay-fronts, 1930s semis in Chingford.

Rear dormerL-shaped dormerHip-to-gable

Planning in Waltham Forest

Walthamstow Village conservation area is strict; elsewhere planning is workmanlike. E17 rear dormers are very common and well-precedented.

Party Wall Act — what to expect

Terrace stock: two party wall notices are standard.

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

Typical costs in Waltham Forest

For a mid-spec 25 m² rear dormer loft conversion, all-in (structural design, building control, party wall, VAT and 12% contingency), expect roughly £105,000 to £160,000. 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
Inner London · +2% vs London average

Our calculator applies a 1.02× multiplier automatically for Waltham Forest projects. Get an itemised breakdown in 60 seconds.

Get your Waltham Forest estimate

Areas we cover in Waltham Forest

E4E10E11E17

Why homeowners in Waltham Forest pick us

  • KYB-verified builders only
  • Local Waltham Forest project experience
  • Fixed, itemised written quotes
  • Full insurance & warranty checks
Call now WhatsApp