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 £1,496
Ballantine building solutions is an established extension buildering business in Holywood. We come highly recommended and provide competitive quote...
From £1,584
Designco Ltd is an established extension buildering business in Holywood. We come highly recommended and provide competitive quotes for your work.<...
From £1,464
Trusted and professional extension builder in Holywood. Experienced in all extension buildering work and keeping within budget and on quote. DGA ha...
From £1,576
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £1,376
Trusted and professional extension builder in Holywood. Experienced in all extension buildering work and keeping within budget and on quote. Extend...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in Holywood it ranges from £1,376 (Extended living by Gilbert-Ash based in BT12) to £1,584 (Designco Ltd based in BT36).
Comparing extension builders estimates for fitting an RSJ gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
Get rates and quotes to install an RSJ 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 |
|---|---|---|
| Install An RSJ near Holywood | £23 | £159 |
| Install An RSJ near Greenisland | £23 | £153 |
| Install An RSJ near Belfast | £23 | £161 |
| Install An RSJ near Carrickfergus | £23 | £158 |
| Install An RSJ near Bangor | £24 | £183 |
| Install An RSJ near Bangor | £24 | £183 |
| Install An RSJ near Ballygowan | £24 | £183 |
| Install An RSJ near Comber | £22 | £160 |
| Install An RSJ near Carryduff | £23 | £158 |
| Install An RSJ 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