Everything we know about house extensions in London, in one place.
This page is the deep-dive index for House Extensions. Read it linearly or jump to the section you need.
Three common drivers in London: family-growth space pressure, value uplift on Victorian/Edwardian stock, and rising rent making moving up the ladder uneconomic. House Extensions captures all three.
For most London homes that aren't flats, listed or in conservation areas, house extensions qualifies under Permitted Development. The house extension drawings test: under volume threshold, materials match, eaves setback. Where Article 4 applies, the LDC route gives certainty before building. Where conservation rules apply, full planning is required.
Part L (thermal), Part B (fire), Part M (access), Part K (stairs/falls), Part E (acoustic), Part F (ventilation). Each governs a different aspect of the house extension drawings. Sign-off via LABC or Approved Inspector.
Drawings: fixed fee from £1,225. Council fees: £103-£206. Building regs fees: £400-£900. Structural engineer: £800-£1,500. Party Wall surveyor (where applicable): £450-£1,500/neighbour. Build cost: separate quote from a contractor.
Wrong PD assumption (Article 4 area). Material non-match in conservation areas. Insufficient Heritage Statement detail on listed property. Missing Party Wall notice triggering legal injunction. We solve all of these as standard.