Relax... you have found a reliable extension builder in Holywood. SM Plumbing & Heating is a friendly and reliable company based in Holywood who co...
From £16,796
Ballantine building solutions is an established extension buildering business in Holywood. We come highly recommended and provide competitive quote...
From £16,884
Designco Ltd is an established extension buildering business in Holywood. We come highly recommended and provide competitive quotes for your work.<...
From £16,764
Trusted and professional extension builder in Holywood. Experienced in all extension buildering work and keeping within budget and on quote. DGA ha...
From £16,876
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £16,676
Trusted and professional extension builder in Holywood. Experienced in all extension buildering work and keeping within budget and on quote. Extend...

Underpinning ranges from £16,676 (Extended living by Gilbert-Ash based in BT12) to £16,884 (Designco Ltd based in BT36), 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 Holywood by posting a job with HaMuch and we will send it to extension builders in Holywood.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Underpin A Building near Holywood | £23 | £159 |
| Underpin A Building near Greenisland | £23 | £153 |
| Underpin A Building near Belfast | £23 | £161 |
| Underpin A Building near Carrickfergus | £23 | £158 |
| Underpin A Building near Bangor | £24 | £183 |
| Underpin A Building near Bangor | £24 | £183 |
| Underpin A Building near Ballygowan | £24 | £183 |
| Underpin A Building near Comber | £22 | £160 |
| Underpin A Building near Carryduff | £23 | £158 |
| Underpin A Building near Ballyclare | £20 | £124 |
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 - £16,811

Two storey extension - £86,966

Build a timber frame extension - £25,311

Build a swimming pool - £80,311

Single storey extension - £41,213

Side return extension - £33,745

Install an RSJ - £1,511

Outbuilding - £9,311

Build a Mansard loft conversion - £51,311

Loft conversion - £27,288

Build a kitchen extension - £41,311

Hip to gable loft conversion - £41,311

Granny annexe - £86,311

Garden office - £9,311

Convert a Garage - £15,311

Garage - £17,811

Build a flat roof extension - £21,311

Build a dormer loft conversion - £41,311

Concrete foundations - £5,561

Convert a bungalow loft - £28,311

Convert a basement - £29,745