From £10,104
London, W4
Starling Constructions Ltd is an established and experienced local extension builder in W4. Please contact us for a free, no obligation quote and c...
From £10,488
Greater London, W4
Kuta Design and Build Limited is an established and experienced local extension builder in W4. Please contact us for a free, no obligation quote an...
From £10,304
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £10,024
Greater London, W4
Relax... you have found a reliable extension builder in W4. Elite London Construction is a friendly and reliable company based in W4 who consider n...
From £10,152
Good Design and Build are here to help customers who need an Extension Builder in W4. We offer a competitive rate to complete all your extension bu...
From £10,216
Londonderry, W4
Guardian Developments is a west London based design and build company, specialising in residential projects including extensions, refurbishments a...
From £10,080
Relax... you have found a reliable extension builder in W4. Zulufish is a friendly and reliable company based in W4 who consider no job as too big ...
From £10,336
Midlothian, W4
Smart Property Sourcing is a trusted extension builder serving customers in W4 and the surrounding area. Contact us to today to get a competitive q...
From £10,064
Pipedreams Interiors Ltd are here to help customers who need an Extension Builder in W4. We offer a competitive rate to complete all your extension...

Outbuilding costs in W4 range from the cheapest of £10,000 (SxS Design & Build based in W4) to the dearest of £10,488 (Kuta Design and Build Limited based in W4), but these are just estimates.
Comparing extension builders estimates for building an outbuilding gives you an idea of who will be better value, but the best way to compare costs is to get actual quotes.
Get rates and quotes to build an outbuilding in W4 by posting a job with HaMuch and we will send it to extension builders.
| Borough in London |
|---|
| Outbuilding in Chiswick |
| Outbuilding in Acton |
| Outbuilding in Barnes |
| Outbuilding in Hammersmith |
| Outbuilding in Mortlake |
| Outbuilding in Shepherd's Bush |
| Outbuilding in Brentford |
| Outbuilding in Kew |
| Outbuilding in Ealing |
| Outbuilding in West Kensington |
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 - £17,677

Two storey extension - £88,265

Build a timber frame extension - £26,177

Build a swimming pool - £81,177

Single storey extension - £58,536

Side return extension - £43,489

Install an RSJ - £2,377

Outbuilding - £10,177

Build a Mansard loft conversion - £52,177

Loft conversion - £35,408

Build a kitchen extension - £42,177

Hip to gable loft conversion - £42,177

Granny annexe - £87,177

Garden office - £10,177

Convert a Garage - £16,177

Garage - £18,677

Build a flat roof extension - £22,177

Build a dormer loft conversion - £42,177

Concrete foundations - £6,427

Convert a bungalow loft - £29,177

Convert a basement - £39,489