From £16,932
WJ Builders is an established and experienced local extension builder in Harlech. Please contact us for a free, no obligation quote and competitive...
From £16,756
Building & Flat Roofing Contractors is a trusted extension builder serving customers in Harlech and the surrounding area. Contact us to today to ge...

Underpinning ranges from £16,756 (Building & Flat Roofing Contractors based in LL54) to £16,932 (WJ Builders based in LL53), but the final cost will depend on the method of underpinning used, how much of your foundations need underpinning and where you live.
Comparing extension builders estimates for underpinning gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
Get quotes to underpin your home in Harlech by posting a job with HaMuch and we will send it to extension builders in Harlech.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Conwy | £28 | £211 |
| Underpin A Building near Conway | £28 | £211 |
| Underpin A Building near Colwyn Bay | £28 | £211 |
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.

Underpin a building - £16,844

Two storey extension - £87,016

Build a timber frame extension - £25,344

Build a swimming pool - £80,344

Single storey extension - £41,880

Side return extension - £34,120

Install an RSJ - £1,544

Outbuilding - £9,344

Build a Mansard loft conversion - £51,344

Loft conversion - £27,600

Build a kitchen extension - £41,344

Hip to gable loft conversion - £41,344

Granny annexe - £86,344

Garden office - £9,344

Convert a Garage - £15,344

Garage - £17,844

Build a flat roof extension - £21,344

Build a dormer loft conversion - £41,344

Concrete foundations - £5,594

Convert a bungalow loft - £28,344

Convert a basement - £30,120