Affordable B21 Extension Builders from £24/hr

Find affordable B21 extension builders now

Extension builders rates in B21 range from £24/hour £196/day (Dave Mattock) to £43/hour £375/day (TG Building Services & Son). To see prices and availability now for your job click green button.

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"Build a kitchen extension" - B8, job posted 16/09/26

"Install an RSJ. For bow window replacement" - WS5, job posted 15/09/26

"Loft conversion" - WS10, job posted 08/05/26

"Loft conversion" - B68, job posted 06/05/26

"RSJ installation" - BIRMINGHAM, job posted 13/04/26

"Dormer loft conversion" - B62, job posted 17/03/26

"Door into garagefrom kitchen how much" - B74, job posted 20/02/26

"Garage conversion (separate from main house) into a bedroom" - B42, job posted 17/02/26

"Garden self contained annex" - B68, job posted 10/11/25

"Two storey extension" - WEST MIDLANDS, job posted 05/10/25

"Concrete foundation" - B29, job posted 03/09/25

"New Wetroom for special needs with wheelchair access. Complete build with material,plumbing,wall panels,floor tiles.shower, toilet etc.this will be built joined with a living room. Quotes required.Thanks" - SANDWELL, job posted 26/08/25

"Two storey extension" - WEST MIDLANDS, job posted 03/08/25

"Two storey extension" - B68, job posted 21/07/25

"Need an extension builder" - SANDWELL, job posted 13/06/25

"Two storey extension" - WEST MIDLANDS, job posted 08/06/25

"Side return extension" - BIRMINGHAM, job posted 24/02/25

"Build an outbuilding" - B44, job posted 15/02/25

"WET ROOM WITH WHEELCHAIR ACCESS" - SANDWELL, job posted 05/02/25

"2 metres front extension and 3 meters back extension" - WS1, job posted 07/01/25

Compare B21 extension builders rates

Compare B21 extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Smethwick	£29	£230
Extension Builders near Birmingham	£28	£228
Extension Builders near West Bromwich	£29	£228
Extension Builders near Oldbury	£29	£229
Extension Builders near Sandwell	£29	£231
Extension Builders near Rowley Regis	£29	£228
Extension Builders near Wednesbury	£29	£230
Extension Builders near Tipton	£29	£228
Extension Builders near Halesowen	£28	£225
Extension Builders near Walsall	£29	£229

Job estimates from extension builders near you

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.

Build a timber frame extension - £25,864

Garden office - £9,864

Granny annexe - £86,864

Build a flat roof extension - £21,864

Convert a Garage - £15,864

Hip to gable loft conversion - £41,864

Convert a bungalow loft - £28,864

Build a dormer loft conversion - £41,864

Build a swimming pool - £80,864

Build a Mansard loft conversion - £51,864

Concrete foundations - £6,114

Underpin a building - £17,364

Two storey extension - £87,796

Convert a basement - £35,970

Side return extension - £39,970

Loft conversion - £32,475

Garage - £18,364

Single storey extension - £52,280

Outbuilding - £9,864

Install an RSJ - £2,064

Build a kitchen extension - £41,864

More extensions & conversions cost guides...

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