Home Extension Builders in Lewisham

Home extension cost in Lewisham typically ranges from £45,000 to £110,000+. A single-storey rear extension (3m x 4m) costs £45,000–£65,000, larger single-storey extensions run £65,000–£85,000, side returns £35,000–£55,000, and double-storey extensions £85,000–£110,000+. Costs vary based on groundworks, finishes, and structural requirements. Buildaway provides full itemised home extension cost Lewisham breakdowns before work begins.

Home extension cost in Lewisham runs 15–20% above the UK national average, reflecting South East London labour and material rates across SE13 and SE6. A single-storey rear extension averaging £35,000–£50,000 nationally sits at £45,000–£65,000 in Lewisham. Buildaway offers transparent, no-hidden-fee estimates throughout.

Most home extensions in Lewisham complete within 12 to 20 weeks. Single-storey rear extensions take 12–14 weeks, side returns 10–12 weeks, and double-storey extensions 16–20 weeks. Party wall agreements — common across Lewisham's terraced streets — and planning permissions may extend lead times. Buildaway provides clear programme dates from the outset and keeps communication consistent throughout.

Buildaway offers single-storey rear extensions, side return extensions, double-storey additions, wrap-around extensions, and garage conversions across Lewisham. Our home extension specialists assess your property's layout, boundary conditions, and local planning requirements before recommending the right approach and producing tailored home extension plans in Lewisham.

We open with a free site survey covering structure, boundaries, drainage, and any planning requirements specific to Lewisham. We discuss your home extension ideas and establish realistic costs for your property type. Buildaway then prepares all architectural drawings, structural calculations, and manages submissions to Lewisham Council — right through to Building Control completion certificates.

Yes — our in-house team of architects, structural engineers, and tradespeople handles everything: planning applications, party wall agreements, Building Control submissions, and all construction trades including groundworks, brickwork, roofing, carpentry, electrics, plumbing, and plastering. As a fully integrated home extension company in Lewisham, you have one point of contact from initial consultation to final handover.