From £17,476
A to Z Builders Ltd are here to help customers who need an Extension Builder in Belgravia. We offer a competitive rate to complete all your extensi...
From £17,756
F & F Building Services is an established extension buildering business in Belgravia. We come highly recommended and provide competitive quotes for...
From £15,708
Here at London Design and Build, our team of architects, interior designers, structural engineers and contractors, offer a bespoke, turn-key servic...
From £17,492
Relax... you have found a reliable extension builder in Belgravia. London Projects Ltd is a friendly and reliable company based in Belgravia who co...
From £17,836
Luxury Movement is an established extension buildering business in Belgravia. We come highly recommended and provide competitive quotes for your wo...
From £17,820
Cliden Construction (London) is a trusted extension builder serving customers in Belgravia and the surrounding area. Contact us to today to get a c...
From £17,884
Experienced extension builder ready to quote for your work. Future Homes Design and Build is the best extension builder in Belgravia. No obligation...
From £17,524
At Alt Construction we provide a complete and professional turnkey construction service for internal alterations, extensions, including detailed de...
From £17,604
Trusted and professional extension builder in Belgravia. Experienced in all extension buildering work and keeping within budget and on quote. The M...
From £17,892
Trusted and professional extension builder in Belgravia. Experienced in all extension buildering work and keeping within budget and on quote. Prope...

Underpinning ranges from £15,708 (London Design And Build based in SW1A) to £17,892 (Property Refurbishment London based in SW1X), but the final cost will depend on the method of underpinning used, how much of your foundations need underpinning and where you live.
Comparing extension builders estimates for underpinning gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
Get quotes to underpin your home in Belgravia by posting a job with HaMuch and we will send it to extension builders in Belgravia.
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 - £17,499

Two storey extension - £87,999

Build a timber frame extension - £25,999

Build a swimming pool - £80,999

Single storey extension - £54,984

Side return extension - £41,491

Install an RSJ - £2,199

Outbuilding - £9,999

Build a Mansard loft conversion - £51,999

Loft conversion - £33,743

Build a kitchen extension - £41,999

Hip to gable loft conversion - £41,999

Granny annexe - £86,999

Garden office - £9,999

Convert a Garage - £15,999

Garage - £18,499

Build a flat roof extension - £21,999

Build a dormer loft conversion - £41,999

Concrete foundations - £6,249

Convert a bungalow loft - £28,999

Convert a basement - £37,491