Building & Construction in London

Finding a Builder in London

From loft conversions in Islington to rear extensions in Bromley, London's builders are accustomed to working in complex planning environments. Many properties across the capital sit in conservation areas or are listed buildings, meaning permitted development rights may be restricted. It's advisable to choose a builder who has direct experience with the London Borough planning process and who can liaise with planning officers or structural engineers on your behalf when needed.

What to Expect on Price

Building costs in London run broadly 20–30% above the national average. A single-storey rear extension typically costs £30,000–£60,000, depending on specification and location. Loft conversions range from £40,000 for a basic dormer to over £80,000 for a full mansard in prime central areas. Day rates for general builders run £200–£350, while specialist trades such as structural brickwork or underpinning command higher fees. Always budget a 10–15% contingency for a London project.

Tips for Hiring

Ask for a fully itemised quote — not just a lump sum — so you can compare like-for-like across contractors. Check whether the builder carries public liability insurance (minimum £2 million is standard) and employers' liability insurance if they use subcontractors. For projects over £10,000, consider using a JCT Minor Works contract to protect both parties. Membership of the Federation of Master Builders (FMB) provides an additional layer of accountability and access to a dispute resolution service.