Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.8 (5 reviews)

Find affordable Gwent extension builders

Extension builders rates in Gwent range from £20/hour £150/day (A.Gaddarn Builders) to £36/hour £249/day (PARTRIDGE - WILSON BUILDERS). To see prices and availability now for your job click Get quotes.

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"Timber frame extension" - CF3, job posted 11/02/26

"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 Gwent extension builders rates

Compare Gwent extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Newport	£41	£233
Extension Builders near Risca	£32	£218
Extension Builders near Cwmbran	£43	£219
Extension Builders near Caerphilly	£33	£208
Extension Builders near Cardiff	£34	£219
Extension Builders near Pontypool	£30	£210
Extension Builders near Church Village	£34	£214
Extension Builders near Penarth	£35	£219
Extension Builders near Pontypridd	£33	£211
Extension Builders near Clevedon	£32	£243

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 - £25,760

Garden office - £9,760

Granny annexe - £86,760

Build a flat roof extension - £21,760

Convert a Garage - £15,760

Hip to gable loft conversion - £41,760

Convert a bungalow loft - £28,760

Build a dormer loft conversion - £41,760

Build a swimming pool - £80,760

Build a Mansard loft conversion - £51,760

Concrete foundations - £6,010

Underpin a building - £17,260

Two storey extension - £87,640

Convert a basement - £34,800

Side return extension - £38,800

Loft conversion - £31,500

Garage - £18,260

Single storey extension - £50,200

Outbuilding - £9,760

Install an RSJ - £1,960

Build a kitchen extension - £41,760

More extensions & conversions cost guides...

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