The 10 extension builders from Google's results for Clapham, ranked on Google rating, online presence and other factors. Updated 10 September 2026.
on GoogleLondon
Benchmark Lofts builds home extensions and carries out loft conversions in Clapham and across London. The company works on residential projects to alter internal layouts and create additional living space.
020 7438 2043 207 Ivydale Rd, London SE15 3DY
on GoogleLondon
Alstruct Ltd provides house extensions, loft conversions and basement conversions for homeowners in Chiswick and West London. Its services also include groundworks, full property renovations and garden landscaping.
020 8080 8240 15B Raven Rd, London E18 1HB
on GooglePopes Dr, London
LCCL Construction is a design and build company converting lofts, extending houses and renovating homes across East London. It works in areas such as Hackney, Walthamstow, Leyton and Bow, where much of the housing is Victorian terraces, and provides architectural design as part of its service.
020 8037 7332 3rd Floor, Hathaway House, Popes Dr, London N3 1QF
on GoogleConcorde Rd, Maidenhead
Welove Build designs and constructs rear home extensions alongside internal property refurbishments. Located in Maidenhead, the firm handles residential building projects across London, including work on Victorian homes in Clapham Common.
07724 595976 Concorde Park, Concorde Rd, Maidenhead SL6 4FJ
on GoogleLondon
Hampstead Renovations plans and coordinates residential extension projects for homeowners located in Wandsworth Town. The firm provides planning guidance, builder briefing support, and project management for house expansions across the SW18 area.
020 7101 3168 Palace Court, 250, Unit 3 Finchley Rd, London NW3 6DN
on GoogleDungiven, Londonderry
Farren Architects designs house extensions and reconfigurations, creating open-plan kitchen and living spaces. Work includes single-storey extensions, glazed openings, carports and patio areas. The practice undertakes projects in Belfast and across Northern Ireland.
028 7774 0643 447 Ballyquin Rd, Dungiven, Londonderry BT47 4LX
on GoogleLondon
Providing architectural services for domestic extension projects, this practice prepares site surveys, planning submissions, and building regulation approvals. Recent schemes include side extensions, kitchen expansions, and internal alterations for terraced properties in Clapham North.
020 3984 3005 86-90 Paul St, London EC2A 4NE
on GoogleClapham
Simply Extend builds house and kitchen extensions across East and South London, covering areas such as Croydon, Lambeth and Wandsworth. The business manages residential builds through assigned project managers, handling groundworks, brickwork construction, plastering and internal fittings.
Clapham
Kitchen Design Chiswick supplies kitchen fitting and extension building services in Chiswick.
London
Dps co carries out house extensions and loft conversions across London and Surrey. Recent work includes Velux and dormer conversions in Wandsworth to create additional bedroom spaces.
020 8395 8847 93 Upper Richmond Rd, London SW15 2TG
In Clapham, single storey, per m² typically costs £2,200 – £3,000. Labour in Greater London runs 21% above the UK median, which accounts for most of the difference from the same job elsewhere.
These are the firms from Google's results for "house extensions clapham". They are ranked on Google rating, online presence and other factors.
The figures above are Clapham ranges. These explain what drives them, so you can read a quote properly.
Per-square-metre prices for single-storey, two-storey, side return and kitchen extensions, costs by size, the fees outside the build price, and planning limits by nation.
The permitted development limits for extensions, lofts, porches and outbuildings in England, where the rights do not apply, what prior approval and a certificate cost, and how Wales, Scotland and NI differ.
When the Party Wall Act applies, which notice to serve and how far ahead, what your neighbour can do, what a surveyor's award costs, and the rules in Scotland and NI.
Under permitted development, three metres for a terrace or semi and four for a detached, doubled to six and eight under the prior approval process. Height, materials and how much garden you cover all carry separate limits, and none of it applies in a conservation area.
If you are excavating within three metres of a neighbour's foundations or building on the boundary, yes. You must serve notice two months before work starts. Skipping it is the most common reason extension projects stall.