From £2,024
Relax... you have found a reliable extension builder in DN12. Foundation Building Services is a friendly and reliable company based in DN12 who con...
From £2,208
We are a family run business with 20 years experience.
We take great care and attention to the work we carry out and pride ourselves on ...
From £2,168
Relax... you have found a reliable extension builder in DN12. CS Construction & Conversions is a friendly and reliable company based in DN12 who co...
From £2,136
Dore Decor are a family run business with over 30 years experience - we offer an extensive range of building services and are able to provide a ful...
From £2,312
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £2,544
Trusted and professional extension builder in DN12. Experienced in all extension buildering work and keeping within budget and on quote. AMB Joiner...
From £2,288
Hallamshire Paving is an established and experienced local extension builder in DN12. Please contact us for a free, no obligation quote and competi...
From £2,184
BP Builders are here to help customers who need an Extension Builder in DN12. We offer a competitive rate to complete all your extension buildering...
From £2,064
Trusted and professional extension builder in DN12. Experienced in all extension buildering work and keeping within budget and on quote. MGG CONSTR...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in DN12 it ranges from £1,488 (JON WINDLE CONSTRUCTION based in S17) to £2,544 (AMB Joinery & Building Services based in S8).
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 DN12 by posting a job with HaMuch and we will send it to extension builders in DN12.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near Doncaster | £29 | £238 |
| Install An RSJ near Wickersley | £33 | £257 |
| Install An RSJ near Rotherham | £33 | £257 |
| Install An RSJ near Barnsley | £31 | £242 |
| Install An RSJ near Sheffield | £32 | £261 |
| Install An RSJ near Worksop | £33 | £265 |
| Install An RSJ near Pontefract | £30 | £228 |
| Install An RSJ near Bassetlaw | £31 | £243 |
| Install An RSJ near Retford | £31 | £243 |
| Install An RSJ near Dronfield | £33 | £262 |
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 - £17,442

Two storey extension - £87,912

Build a timber frame extension - £25,942

Build a swimming pool - £80,942

Single storey extension - £53,832

Side return extension - £40,843

Install an RSJ - £2,142

Outbuilding - £9,942

Build a Mansard loft conversion - £51,942

Loft conversion - £33,203

Build a kitchen extension - £41,942

Hip to gable loft conversion - £41,942

Granny annexe - £86,942

Garden office - £9,942

Convert a Garage - £15,942

Garage - £18,442

Build a flat roof extension - £21,942

Build a dormer loft conversion - £41,942

Concrete foundations - £6,192

Convert a bungalow loft - £28,942

Convert a basement - £36,843