From £1,464
Trusted and professional extension builder in BT38. Experienced in all extension buildering work and keeping within budget and on quote. DGA have m...
From £1,496
Ballantine building solutions is an established extension buildering business in BT38. We come highly recommended and provide competitive quotes fo...
From £1,584
Designco Ltd is an established extension buildering business in BT38. We come highly recommended and provide competitive quotes for your work.
...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 £1,176
Have worked in building industry for over 30 years contracts from government to private sector.
From £1,568
Relax... you have found a reliable extension builder in BT38. SM Plumbing & Heating is a friendly and reliable company based in BT38 who consider n...
From £1,408
Need an Extension Builder in BT38? MIRKOW has been helping local clients (20 mile radius) with their extension buildering jobs for many years. Get ...
From £1,552
Need to find an Extension Builder near you for all your extension buildering work?
Firenstack Solutions provides a local, trusted extension...
From £1,520
C.H Property Services is a trusted extension builder serving customers in BT38 and the surrounding area. Contact us to today to get a competitive q...
From £1,480
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in BT38 it ranges from £1,176 (Anak based in BT40) 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 BT38 by posting a job with HaMuch and we will send it to extension builders in BT38.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near Carrickfergus | £21 | £145 |
| Install An RSJ near Greenisland | £20 | £134 |
| Install An RSJ near Holywood | £20 | £138 |
| Install An RSJ near Bangor | £20 | £150 |
| Install An RSJ near Bangor | £20 | £150 |
| Install An RSJ near Larne | £15 | £120 |
| Install An RSJ near Ballyclare | £17 | £110 |
| Install An RSJ near Belfast | £20 | £137 |
| Install An RSJ near Ballygowan | £20 | £150 |
| Install An RSJ near Comber | £20 | £142 |
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 - £16,782

Two storey extension - £86,924

Build a timber frame extension - £25,282

Build a swimming pool - £80,282

Single storey extension - £40,648

Side return extension - £33,427

Install an RSJ - £1,482

Outbuilding - £9,282

Build a Mansard loft conversion - £51,282

Loft conversion - £27,023

Build a kitchen extension - £41,282

Hip to gable loft conversion - £41,282

Granny annexe - £86,282

Garden office - £9,282

Convert a Garage - £15,282

Garage - £17,782

Build a flat roof extension - £21,282

Build a dormer loft conversion - £41,282

Concrete foundations - £5,532

Convert a bungalow loft - £28,282

Convert a basement - £29,427