From £2,592
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £2,240
Ealing Buckinghamshire, W5
We offer a variety of professional building services from start to finish, providing a complete service so that you don’t need to deal with diffe...
From £2,536
Reliable and experienced extension builders with competitive rates and good at keeping within budget. Happy to provide examples of extension builde...
From £2,336
Ealing Londonderry, W5
Bricks Republic Limited is a trusted extension builder serving customers in Ealing and the surrounding area. Contact us to today to get a competiti...
From £2,424
Need to find an Extension Builder near you for all your extension buildering work?
S. A. W. Building Contractors Ltd. provides a local, tru...
From £2,160
Ealing London, W5
Decozest are a family run west London property development firm specialised in luxury residential property development that's affordable. We offer ...
From £2,472
CORE VALUESConsider honesty as the key to a business’ trustworthiness and integrity.Always do the right thing to solve the customer’s problem.P...
From £2,608
Ealing, W5
Need an Extension Builder in Ealing? WIT CONSTRUCTION has been helping local clients (5 mile radius) with their extension buildering jobs for many ...
From £2,392
Detail D Limited is a trusted extension builder serving customers in Ealing and the surrounding area. Contact us to today to get a competitive quot...
From £2,008
Need an Extension Builder in Ealing? CHURCHWOOD MANAGEMENT LTD has been helping local clients (5 mile radius) with their extension buildering jobs ...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in Ealing it ranges from £2,008 (CHURCHWOOD MANAGEMENT LTD based in W13) to £2,608 (WIT CONSTRUCTION based in W5).
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 Ealing by posting a job with HaMuch and we will send it to extension builders in Ealing.
"UC beam install 2.5m only (calculations done, building control notification done, no pretty boxing etc.)" - TW8, job posted 03/09/26
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 - £17,677

Two storey extension - £88,265

Build a timber frame extension - £26,177

Build a swimming pool - £81,177

Single storey extension - £58,536

Side return extension - £43,489

Install an RSJ - £2,377

Outbuilding - £10,177

Build a Mansard loft conversion - £52,177

Loft conversion - £35,408

Build a kitchen extension - £42,177

Hip to gable loft conversion - £42,177

Granny annexe - £87,177

Garden office - £10,177

Convert a Garage - £16,177

Garage - £18,677

Build a flat roof extension - £22,177

Build a dormer loft conversion - £42,177

Concrete foundations - £6,427

Convert a bungalow loft - £29,177

Convert a basement - £39,489