From £1,632
We have over 25 years experience in all building work and renowned for good workmanship All jobs small and large taken on
From £1,496
Been in business as 18 years alway put clients first and never had any combacks
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 £1,696
Trusted and professional extension builder in BT42. Experienced in all extension buildering work and keeping within budget and on quote. purdy buil...
From £1,464
Trusted and professional extension builder in BT42. Experienced in all extension buildering work and keeping within budget and on quote. DGA have m...
From £2,104
FJS CONTRACTS LTD are here to help customers who need an Extension Builder in BT42. We offer a competitive rate to complete all your extension buil...
From £1,496
Ballantine building solutions is an established extension buildering business in BT42. We come highly recommended and provide competitive quotes fo...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in BT42 it ranges from £1,176 (Anak based in BT40) to £2,104 (FJS CONTRACTS LTD based in BT45).
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 BT42 by posting a job with HaMuch and we will send it to extension builders in BT42.
"RSJ installation, I am looking for a price to source and install two beams, photos attached of measurements. Thanks." - BT43
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near Ballyclare | £17 | £110 |
| Install An RSJ near Magherafelt | £25 | £200 |
| Install An RSJ near Crumlin | £22 | £168 |
| Install An RSJ near Ballymoney | £18 | £163 |
| Install An RSJ near Larne | £15 | £120 |
| Install An RSJ near Greenisland | £20 | £134 |
| Install An RSJ near Coleraine | £21 | £181 |
| Install An RSJ near Carrickfergus | £21 | £145 |
| Install An RSJ near Belfast | £20 | £137 |
| Install An RSJ near Holywood | £20 | £138 |
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 - £16,880

Two storey extension - £87,070

Build a timber frame extension - £25,380

Build a swimming pool - £80,380

Single storey extension - £42,600

Side return extension - £34,525

Install an RSJ - £1,580

Outbuilding - £9,380

Build a Mansard loft conversion - £51,380

Loft conversion - £27,938

Build a kitchen extension - £41,380

Hip to gable loft conversion - £41,380

Granny annexe - £86,380

Garden office - £9,380

Convert a Garage - £15,380

Garage - £17,880

Build a flat roof extension - £21,380

Build a dormer loft conversion - £41,380

Concrete foundations - £5,630

Convert a bungalow loft - £28,380

Convert a basement - £30,525