Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.73 (20 reviews)

Find affordable B12 extension builders

Extension builders rates in B12 range from £25/hour £199/day (Fletchers Building & Maintenance, Ltd.) to £33/hour £256/day (Darthy serices and cleaning). 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 shade in the garden." - B92, job posted 05/09/26

"Build a kitchen extension" - B13, job posted 28/08/26

"Refurb whole house" - B92, job posted 09/08/26

"Garage conversion" - B92, job posted 02/06/26

"Loft conversion" - B30, job posted 26/05/26

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

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

"RSJ installation" - B90, job posted 08/03/26

"Rear single storey extension 18sm kitchen & shower room with 2 beams" - B36, job posted 26/11/25

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

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

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

"Timber frame extension At present there is a side garage which is in a state of disrepair, on a lower height to the house. Ideally we would like to have a wooden extension along the complete side of the house at the same height as the house, as well as across the rear of the house. We would also..." - B26, job posted 18/07/25

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

"Loft conversion" - B28, job posted 26/05/25

"Rear extension to incorporate toilet and downstairs shower, utility area." - SHELDON, job posted 21/03/25

"We would like a builder for a 3m extension to the back of our house (similar to a conservatory)." - B30, job posted 15/03/25

"TV aerial install" - B11, job posted 05/03/25

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

What are the best ways to avoid problems when paying the Extension Builder?

The most important thing is do avoid handing over cash or paying large sums in advance. Be wary of paying cash for a cheaper job, i.e. to avoid VAT, you may be going down a slippery slope of not doing things properly which may eventually mean your job is also not done properly.

Agree when you intend to pay, ideally after you are satisfied with the completed job. If it is a big job agree a schedule of staged payments which is fair to both parties.

To avoid bad tradespeople and to ensure you can find them should they not answer a mobile;

Get proper contact details and check them yourself
Check if the company is verified on the Companies House website
Get phone details, ideally a land line or 0800 number and check it
Get a physical office address

Before the job starts should I agree standards of quality and behaviour?

Get quotes in writing by email or in person if possible. Getting quotes online or by text is ok (make sure you accept the offer by replying). For large projects make a written agreement, schedule of works and snagging plans as part of a working document. Also;

Agree expected quality of workmanship and materials in advance
When will work start and when will project be finished, what happens if project over runs ?
How long is the guarantee on work and materials eg 12 months
Discuss onsite behaviour in advance (no smoking, swearing or using mobile phones for non-work purposes)
Agree that your Extension Builder will remove all debris and rubbish and what level of tidying up you want after job

Compare B12 extension builders rates

Compare B12 extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Birmingham	£28	£226
Extension Builders near Smethwick	£29	£225
Extension Builders near Oldbury	£29	£226
Extension Builders near Solihull	£29	£231
Extension Builders near Halesowen	£28	£225
Extension Builders near West Bromwich	£28	£225
Extension Builders near Sutton Coldfield	£29	£228
Extension Builders near Rowley Regis	£29	£225
Extension Builders near Sandwell	£29	£228
Extension Builders near Knowle	£31	£241

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 - £25,848

Garden office - £9,848

Granny annexe - £86,848

Build a flat roof extension - £21,848

Convert a Garage - £15,848

Hip to gable loft conversion - £41,848

Convert a bungalow loft - £28,848

Build a dormer loft conversion - £41,848

Build a swimming pool - £80,848

Build a Mansard loft conversion - £51,848

Concrete foundations - £6,098

Underpin a building - £17,348

Two storey extension - £87,772

Convert a basement - £35,790

Side return extension - £39,790

Loft conversion - £32,325

Garage - £18,348

Single storey extension - £51,960

Outbuilding - £9,848

Install an RSJ - £2,048

Build a kitchen extension - £41,848

More extensions & conversions cost guides...

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