Mandala Building Services is a family-owned design and build maintenance company, encompassing everything from residential refurbishment to large-s...
Peter Rourke
Trusted and professional extension builder in St Albans. Experienced in all extension buildering work and keeping within budget and on quote. Peter...
Amarjeet Gill
Architecture and Construction all in one place.
FREE DRAWINGS for all projects we build.
At One Call Bathrooms we can tailor our service to provide a bespoke service to all Landlords and Management Agents that will guar...
Buyerz Trading is an established and experienced local extension builder in St Albans. Please contact us for a free, no obligation quote and compet...
Are you looking for resin driveways in North London? We are a leading builder of driveways and patios in North London. We have expertise in various...
Trusted and professional extension builder in St Albans. Experienced in all extension buildering work and keeping within budget and on quote. Advan...
IC Builders have been helping customers in St Albans and the surrounding area by providing professional, trustworthy building services.We k...
London Elite Construction is an established extension buildering business in St Albans. We come highly recommended and provide competitive quotes f...
BSL are here to help customers who need an Extension Builder in St Albans. We offer a competitive rate to complete all your extension buildering jo...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in St Albans it ranges from £2,064 (Advance Construction Solutions based in EN6) to £2,736 (R. Newman Construction based in AL4).
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 St Albans by posting a job with HaMuch and we will send it to extension builders in St Albans.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near St Albans | £63 | £289 |
| Install An RSJ near Harpenden | £87 | £317 |
| Install An RSJ near Hatfield | £65 | £285 |
| Install An RSJ near Hemel Hempstead | £42 | £270 |
| Install An RSJ near Dacorum | £42 | £269 |
| Install An RSJ near Borehamwood | £42 | £271 |
| Install An RSJ near Welwyn Garden City | £42 | £269 |
| Install An RSJ near Bushey | £42 | £276 |
| Install An RSJ near Watford | £43 | £278 |
| Install An RSJ near Potters Bar | £43 | £273 |
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 - £17,746

Two storey extension - £88,370

Build a timber frame extension - £26,246

Build a swimming pool - £81,246

Single storey extension - £59,928

Side return extension - £44,272

Install an RSJ - £2,446

Outbuilding - £10,246

Build a Mansard loft conversion - £52,246

Loft conversion - £36,060

Build a kitchen extension - £42,246

Hip to gable loft conversion - £42,246

Granny annexe - £87,246

Garden office - £10,246

Convert a Garage - £16,246

Garage - £18,746

Build a flat roof extension - £22,246

Build a dormer loft conversion - £42,246

Concrete foundations - £6,496

Convert a bungalow loft - £29,246

Convert a basement - £40,272