SLS BUILDERS LIMITED is a trusted extension builder serving customers in W1U and the surrounding area. Contact us to today to get a competitive quo...
Jay Reid
CK Constructions & Development Ltd is a trusted extension builder serving customers in W1U and the surrounding area. Contact us to today to get a c...
A to Z Builders Ltd are here to help customers who need an Extension Builder in W1U. We offer a competitive rate to complete all your extension bui...
JK Doors is a trusted extension builder serving customers in W1U and the surrounding area. Contact us to today to get a competitive quote for exten...
JM Building Services is a trusted extension builder serving customers in W1U and the surrounding area. Contact us to today to get a competitive quo...
Hussein Eljhani
We are highly professional Builders Company, hones pricing and reliable, we leave all areas clean and tidy.
Buildwiser is a trusted extension builder serving customers in W1U and the surrounding area. Contact us to today to get a competitive quote for ext...
F & F Building Services is an established extension buildering business in W1U. We come highly recommended and provide competitive quotes for your ...
Anthony Sullivan
We build Lofts. We build Extensions. We undertake conversions. Our Terms and conditions apply as shown in our starter packs.

Costs range from £87,964 (SLS BUILDERS LIMITED based in NW5) to £91,480 (Reid and Co Developments Ltd based in NW8), but these are just estimates. The best way to compare costs is to get real quotes from real builders.
Post your job on HaMuch and we'll send it to extension builders to W1U.
Whether you’re looking to extend your kitchen with a side return extension or you want to convert your basement into a liveable space, read our cost guides to get an idea of how much each project costs before getting a more accurate quote from our database of reliable tradespeople.

Underpin a building - £18,085

Two storey extension - £88,877

Build a timber frame extension - £26,585

Build a swimming pool - £81,585

Single storey extension - £66,696

Side return extension - £48,079

Install an RSJ - £2,785

Outbuilding - £10,585

Build a Mansard loft conversion - £52,585

Loft conversion - £39,233

Build a kitchen extension - £42,585

Hip to gable loft conversion - £42,585

Granny annexe - £87,585

Garden office - £10,585

Convert a Garage - £16,585

Garage - £19,085

Build a flat roof extension - £22,585

Build a dormer loft conversion - £42,585

Concrete foundations - £6,835

Convert a bungalow loft - £29,585

Convert a basement - £44,079