CK Constructions & Development Ltd is a trusted extension builder serving customers in SW1A and the surrounding area. Contact us to today to get a ...
A to Z Builders Ltd are here to help customers who need an Extension Builder in SW1A. We offer a competitive rate to complete all your extension bu...
Experienced extension builder ready to quote for your work. Cornerstones Construction is the best extension builder in SW1A. No obligation free quo...
JK Doors is a trusted extension builder serving customers in SW1A and the surrounding area. Contact us to today to get a competitive quote for exte...
JM Building Services is a trusted extension builder serving customers in SW1A and the surrounding area. Contact us to today to get a competitive qu...
Buildwiser is a trusted extension builder serving customers in SW1A and the surrounding area. Contact us to today to get a competitive quote for ex...
F & F Building Services is an established extension buildering business in SW1A. 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 £42,152
Plansing Ltd
Experience the best architectural design services with PLANSING, where we flawlessly integrate innovative architectural designer products to bring ...
From £40,208
London Design And Build
Here at London Design and Build, our team of architects, interior designers, structural engineers and contractors, offer a bespoke, turn-key servic...

In SW1A, prices for dormer loft conversions range from £40,208 (London Design And Build based in SW1A) to £44,064 (Q Lofts and Extensions based in EC1R), but how much your conversion costs will vary depending on the size of your property, how easy access to your roof is and what you want to use the space for.
The best way to get an accurate price is to compare quotes from extension builders in SW1A. Post your job on HaMuch now and we'll put you in touch with available extension builders.
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 - £17,652

Two storey extension - £88,228

Build a timber frame extension - £26,152

Build a swimming pool - £81,152

Single storey extension - £58,040

Side return extension - £43,210

Install an RSJ - £2,352

Outbuilding - £10,152

Build a Mansard loft conversion - £52,152

Loft conversion - £35,175

Build a kitchen extension - £42,152

Hip to gable loft conversion - £42,152

Granny annexe - £87,152

Garden office - £10,152

Convert a Garage - £16,152

Garage - £18,652

Build a flat roof extension - £22,152

Build a dormer loft conversion - £42,152

Concrete foundations - £6,402

Convert a bungalow loft - £29,152

Convert a basement - £39,210