Name: Extension Builder
Brand: HaMuch
SKU: extension-renovation
Rating: 4.83 (6 reviews)

Find affordable Welwyn extension builders now

Extension builders rates in Welwyn range from £17/hour £165/day (Complex Construction) to £50/hour £317/day (R. Newman Construction). To see prices and availability now for your job click green button.

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"Outbuilding" - SG2, job posted 01/06/26

"Can i get a builder for an extension quotation please - require 1first floor building on top of my garage and a revamped, heat-proof conservatory if you deal with this - reasonably priced please, thank you." - SG2, job posted 21/04/26

"Single storey extension" - WELWYN, job posted 31/08/25

"I would to build an extension on top of my garage, planning stage at the moment but I would like to have an experienced builders intake, realistic cost analysis with a plan to use the builder throughout too. Thanks." - SG2, job posted 04/06/25

"Front of house extension. End of terrace property." - SG2, job posted 30/04/25

"We are small builders looking quote for foundations ,groundworks and drainage - soakways Thanks Harsha.R" - AL8, job posted 16/02/25

Compare Welwyn extension builders rates

Compare Welwyn extension builders rates (excluding VAT or callout charges)
Location in UK	Hourly Rate	Daily Rate
Extension Builders near Welwyn Garden City	£42	£269
Extension Builders near Hertford	£46	£290
Extension Builders near Hatfield	£42	£266
Extension Builders near Stevenage	£44	£282
Extension Builders near Harpenden	£45	£282
Extension Builders near Hitchin	£43	£283
Extension Builders near East Hertfordshire	£44	£289
Extension Builders near Ware	£47	£296
Extension Builders near St Albans	£43	£272
Extension Builders near North Hertfordshire	£44	£283

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 - £26,232

Garden office - £10,232

Granny annexe - £87,232

Build a flat roof extension - £22,232

Convert a Garage - £16,232

Hip to gable loft conversion - £42,232

Convert a bungalow loft - £29,232

Build a dormer loft conversion - £42,232

Build a swimming pool - £81,232

Build a Mansard loft conversion - £52,232

Concrete foundations - £6,482

Underpin a building - £17,732

Two storey extension - £88,348

Convert a basement - £40,110

Side return extension - £44,110

Loft conversion - £35,925

Garage - £18,732

Single storey extension - £59,640

Outbuilding - £10,232

Install an RSJ - £2,432

Build a kitchen extension - £42,232

More extensions & conversions cost guides...

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