From £2,392
TCL BUILDING SOLUTIONS LTD are here to help customers who need an Extension Builder in SG18. We offer a competitive rate to complete all your exten...
From £2,368
Relax... you have found a reliable extension builder in SG18. Imogen Jack is a friendly and reliable company based in SG18 who consider no job as t...
From £2,336
Trusted and professional extension builder in SG18. Experienced in all extension buildering work and keeping within budget and on quote. J. WATSON ...
From £2,048
Need an Extension Builder in SG18? R&J Building Services Ltd has been helping local clients (20 mile radius) with their extension buildering jobs f...
From £2,320
For more than 10 years, North Hertfordshire Construction LTD have been the name you can trust when it comes to building and development! We are kno...
From £2,464
Relax... you have found a reliable extension builder in SG18. Applewood Design and Build Ltd is a friendly and reliable company based in SG18 who c...
From £2,512
Experienced extension builder ready to quote for your work. Bricklayers is the best extension builder in SG18. No obligation free quotes and many h...
From £2,560
Experienced extension builder ready to quote for your work. Specialist Building Refurbishm is the best extension builder in SG18. No obligation fre...
From £2,488
Realise Your Luxury Dream Home With The Design And Build Partner You Can Trust.At MG Design & Build we have over 25 years of experience in the cons...
From £2,344
A.S. OHM Electrics Ltd is a trusted extension builder serving customers in SG18 and the surrounding area. Contact us to today to get a competitive ...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in SG18 it ranges from £2,048 (R&J Building Services Ltd based in SG17) to £2,560 (Specialist Building Refurbishm based in SG16).
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 SG18 by posting a job with HaMuch and we will send it to extension builders in SG18.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near Biggleswade | £41 | £268 |
| Install An RSJ near Letchworth | £44 | £283 |
| Install An RSJ near North Hertfordshire | £44 | £283 |
| Install An RSJ near Kempston | £44 | £273 |
| Install An RSJ near South Bedfordshire | £45 | £278 |
| Install An RSJ near Bedford | £45 | £278 |
| Install An RSJ near Mid Bedfordshire | £42 | £276 |
| Install An RSJ near Ampthill | £38 | £258 |
| Install An RSJ near St Neots | £51 | £318 |
| Install An RSJ near Hitchin | £43 | £283 |
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 - £17,683

Two storey extension - £88,275

Build a timber frame extension - £26,183

Build a swimming pool - £81,183

Single storey extension - £58,664

Side return extension - £43,561

Install an RSJ - £2,383

Outbuilding - £10,183

Build a Mansard loft conversion - £52,183

Loft conversion - £35,468

Build a kitchen extension - £42,183

Hip to gable loft conversion - £42,183

Granny annexe - £87,183

Garden office - £10,183

Convert a Garage - £16,183

Garage - £18,683

Build a flat roof extension - £22,183

Build a dormer loft conversion - £42,183

Concrete foundations - £6,433

Convert a bungalow loft - £29,183

Convert a basement - £39,561