Jay Reid
CK Constructions & Development Ltd is a trusted extension builder serving customers in W1T 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 W1T. We offer a competitive rate to complete all your extension bui...
JK Doors is a trusted extension builder serving customers in W1T 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 W1T 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 W1T 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 W1T. 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.
From £17,652
Plansing Ltd
Experience the best architectural design services with PLANSING, where we flawlessly integrate innovative architectural designer products to bring ...

Underpinning ranges from £17,476 (A to Z Builders Ltd based in SW1P) to £19,820 (Reid and Co Developments Ltd based in NW8), 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 W1T by posting a job with HaMuch and we will send it to extension builders in W1T.
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 - £18,102

Two storey extension - £88,904

Build a timber frame extension - £26,602

Build a swimming pool - £81,602

Single storey extension - £67,048

Side return extension - £48,277

Install an RSJ - £2,802

Outbuilding - £10,602

Build a Mansard loft conversion - £52,602

Loft conversion - £39,398

Build a kitchen extension - £42,602

Hip to gable loft conversion - £42,602

Granny annexe - £87,602

Garden office - £10,602

Convert a Garage - £16,602

Garage - £19,102

Build a flat roof extension - £22,602

Build a dormer loft conversion - £42,602

Concrete foundations - £6,852

Convert a bungalow loft - £29,602

Convert a basement - £44,277