Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.67 (6 reviews)

Find affordable Swansea extension builders

Prices range from cheapest £25/hour and £197/day (AJB BUILDING MAINTENANCE) to £34/hour and £260/day (HALL & HARRIS CONSTRUCTION) - average £30/hr and £228/day

HaMuch is Excellent

Local Swansea extension builders & latest jobs

"Install an RSJ" - SA5, job posted 11/09/26

"Loft conversion" - SWANSEA, job posted 12/03/25

"Loft conversion with full width dormer on rear. Please don't ring me I've got laryngitis so can't speak." - SWANSEA, job posted 24/09/24

"Side return extension" - SWANSEA, job posted 26/07/24

"Side extension to extend a kitchen 250 cm width 511cm length knocking wall down with tiled roof and velux roof windows. Just looking for quotes for finish to the point where a new kitchen can be added" - SA2, job posted 04/05/24

"Loft conversion" - SWANSEA, job posted 15/04/24

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 Swansea extension builders rates

Compare Swansea extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Swansea	£29	£230
Extension Builders near Gorseinon	£29	£228
Extension Builders near Neath	£30	£225
Extension Builders near Port Talbot	£31	£227
Extension Builders near Llanelli	£29	£231
Extension Builders near Neath Port Talbot	£31	£224
Extension Builders near Pyle	£34	£262
Extension Builders near Maesteg	£38	£283
Extension Builders near Porthcawl	£33	£252
Extension Builders near Bridgend	£32	£200

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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