From £1,336
Need to find an Extension Builder near you for all your extension buildering work?
Mount Oriel Conversions & Extensions provides a local, t...
From £1,376
Trusted and professional extension builder in Carryduff. Experienced in all extension buildering work and keeping within budget and on quote. Exten...
From £1,568
Relax... you have found a reliable extension builder in Carryduff. SM Plumbing & Heating is a friendly and reliable company based in Carryduff who ...
From £1,536
Trusted and professional extension builder in Carryduff. Experienced in all extension buildering work and keeping within budget and on quote. Belfa...
From £1,584
Relax... you have found a reliable extension builder in Carryduff. Finch Construction NI is a friendly and reliable company based in Carryduff who ...
From £1,600
T.I Building is a trusted extension builder serving customers in Carryduff and the surrounding area. Contact us to today to get a competitive quote...
From £1,584
Designco Ltd is an established extension buildering business in Carryduff. We come highly recommended and provide competitive quotes for your work....
From £1,472
apex pharaoh ltd is a trusted extension builder serving customers in Carryduff and the surrounding area. Contact us to today to get a competitive q...
From £1,496
Ballantine building solutions is an established extension buildering business in Carryduff. We come highly recommended and provide competitive quot...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in Carryduff it ranges from £1,336 (Mount Oriel Conversions & Extensions based in BT8) to £1,688 (AK Building Services based in BT8).
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 Carryduff by posting a job with HaMuch and we will send it to extension builders in Carryduff.
"RSJ installation" - BELFAST, job posted 09/08/25
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near Carryduff | £23 | £158 |
| Install An RSJ near Belfast | £23 | £161 |
| Install An RSJ near Saintfield | £23 | £162 |
| Install An RSJ near Lisburn | £24 | £164 |
| Install An RSJ near Comber | £22 | £160 |
| Install An RSJ near Ballygowan | £24 | £183 |
| Install An RSJ near Holywood | £23 | £159 |
| Install An RSJ near Ballynahinch | £19 | £189 |
| Install An RSJ near Hillsborough and Culcavy | £25 | £170 |
| Install An RSJ near Greenisland | £23 | £153 |
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 - £16,824

Two storey extension - £86,986

Build a timber frame extension - £25,324

Build a swimming pool - £80,324

Single storey extension - £41,480

Side return extension - £33,895

Install an RSJ - £1,524

Outbuilding - £9,324

Build a Mansard loft conversion - £51,324

Loft conversion - £27,413

Build a kitchen extension - £41,324

Hip to gable loft conversion - £41,324

Granny annexe - £86,324

Garden office - £9,324

Convert a Garage - £15,324

Garage - £17,824

Build a flat roof extension - £21,324

Build a dormer loft conversion - £41,324

Concrete foundations - £5,574

Convert a bungalow loft - £28,324

Convert a basement - £29,895