From £17,284
JP&S Construction Ltd is an established extension buildering business in Northern Ireland. We come highly recommended and provide competitive quote...
From £17,516
Need to find an Extension Builder near you for all your extension buildering work?
GMC Construction provides a local, trusted extension bui...
From £16,788
We offer a wide range of services completed to a high standard with fully trained personnel
From £17,516
Seamus Mcmullan building and joinery is an established extension buildering business in Northern Ireland. We come highly recommended and provide co...
From £17,404
FJS CONTRACTS LTD are here to help customers who need an Extension Builder in Northern Ireland. We offer a competitive rate to complete all your ex...
From £16,796
Been in business as 18 years alway put clients first and never had any combacks

Underpinning ranges from £16,788 (M & R McElhatton Joinery based in BT76) to £17,516 (GMC Construction based in BT70), 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 Northern Ireland by posting a job with HaMuch and we will send it to extension builders in Northern Ireland.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Dungannon | £30 | £238 |
| Underpin A Building near Coalisland | £27 | £223 |
| Underpin A Building near Magherafelt | £30 | £238 |
| Underpin A Building near Craigavon | £23 | £181 |
| Underpin A Building near Dungiven | £22 | £190 |
| Underpin A Building near Strabane | £27 | £223 |
| Underpin A Building near Waringstown | £23 | £167 |
| Underpin A Building near Londonderry | £24 | £190 |
| Underpin A Building near Newbuildings | £24 | £190 |
| Underpin A Building near Banbridge | £29 | £205 |
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 - £17,217

Two storey extension - £87,576

Build a timber frame extension - £25,717

Build a swimming pool - £80,717

Single storey extension - £49,347

Side return extension - £38,320

Install an RSJ - £1,917

Outbuilding - £9,717

Build a Mansard loft conversion - £51,717

Loft conversion - £31,100

Build a kitchen extension - £41,717

Hip to gable loft conversion - £41,717

Granny annexe - £86,717

Garden office - £9,717

Convert a Garage - £15,717

Garage - £18,217

Build a flat roof extension - £21,717

Build a dormer loft conversion - £41,717

Concrete foundations - £5,967

Convert a bungalow loft - £28,717

Convert a basement - £34,320