From £2,248
Experienced extension builder ready to quote for your work. J&J Building Solutions is the best extension builder in N18. No obligation free quotes ...
From £2,248
Trusted and professional extension builder in N18. Experienced in all extension buildering work and keeping within budget and on quote. WHITE EAGLE...
From £2,592
Need an Extension Builder in N18? Samuele Paolini has been helping local clients (5 mile radius) with their extension buildering jobs for many yea...
From £2,360
Homeowners look no further if you want a qualified extension builder to work in your home. LCD Pixel Construction Ltd are tidy and neat, providing ...
From £2,120
Masonic Plumbing and Heating Ltd are here to help customers who need an Extension Builder in N18. We offer a competitive rate to complete all your ...
From £2,392
Gb construction are here to help customers who need an Extension Builder in N18. We offer a competitive rate to complete all your extension builde...
From £2,384
Experienced extension builder ready to quote for your work. CC&D BUILDING LTD is the best extension builder in N18. No obligation free quotes and m...
From £2,512
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £2,760
Our homes need to be regularly maintained and from time to time they need to be rejuvenated, modernised and enhanced. When it comes to building wor...
From £2,296
Experienced extension builder ready to quote for your work. Mr is the best extension builder in N18. No obligation free quotes and many happy custo...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in N18 it ranges from £2,120 (Masonic Plumbing and Heating Ltd based in BR2) to £2,760 (Rafix Building based in EN4).
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 N18 by posting a job with HaMuch and we will send it to extension builders in N18.
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 - £17,691

Two storey extension - £88,287

Build a timber frame extension - £26,191

Build a swimming pool - £81,191

Single storey extension - £58,824

Side return extension - £43,651

Install an RSJ - £2,391

Outbuilding - £10,191

Build a Mansard loft conversion - £52,191

Loft conversion - £35,543

Build a kitchen extension - £42,191

Hip to gable loft conversion - £42,191

Granny annexe - £87,191

Garden office - £10,191

Convert a Garage - £16,191

Garage - £18,691

Build a flat roof extension - £22,191

Build a dormer loft conversion - £42,191

Concrete foundations - £6,441

Convert a bungalow loft - £29,191

Convert a basement - £39,651