Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.7 (5 reviews)

Find affordable Cwmbran extension builders now

Extension builders rates in Cwmbran range from £20/hour £150/day (A.Gaddarn Builders) to £40/hour £288/day (Carter Thomas Construction Ltd). To see prices and availability now for your job click green button.

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"Loft conversion" - NP44, job posted 29/06/26

"Attic is already converted, but looking to alter to make space more useable. Potentially consider dormer or dormer windows and fitted storage." - NP18, job posted 30/12/25

"Loft conversion" - NEWPORT, job posted 06/03/25

"RSJ installation" - NEWPORT, job posted 16/10/24

"Remove current conservatory and build a small extension 4x4m" - NP19, job posted 01/05/24

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 Cwmbran extension builders rates

Compare Cwmbran extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Cwmbran	£43	£219
Extension Builders near Risca	£32	£218
Extension Builders near Newport	£41	£233
Extension Builders near Pontypool	£30	£210
Extension Builders near Caerphilly	£33	£208
Extension Builders near Ebbw Vale	£30	£217
Extension Builders near Tredegar	£30	£217
Extension Builders near Cardiff	£34	£223
Extension Builders near Pontypridd	£33	£211
Extension Builders near Church Village	£34	£214

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 - £25,792

Garden office - £9,792

Granny annexe - £86,792

Build a flat roof extension - £21,792

Convert a Garage - £15,792

Hip to gable loft conversion - £41,792

Convert a bungalow loft - £28,792

Build a dormer loft conversion - £41,792

Build a swimming pool - £80,792

Build a Mansard loft conversion - £51,792

Concrete foundations - £6,042

Underpin a building - £17,292

Two storey extension - £87,688

Convert a basement - £35,160

Side return extension - £39,160

Loft conversion - £31,800

Garage - £18,292

Single storey extension - £50,840

Outbuilding - £9,792

Install an RSJ - £1,992

Build a kitchen extension - £41,792

More extensions & conversions cost guides...

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