From £2,344
Edwin Lewis Dickinson is a well established company providing all of its customers with the very highest quality of workmanship using only the best...
From £2,128
Our company is built on trust and communication with our clients.We are of firm belief that our customers needs are of the utmost importance.
From £2,256
Relax... you have found a reliable extension builder in Harwich. AP Laflin Builders Ltd is a friendly and reliable company based in Harwich who con...
From £1,752
Qualified stonerestorer 35years experience own public liability insurance.
Worked on numerous listedbuilding through out &nb...
From £1,872
Experienced extension builder ready to quote for your work. A M F BUILDING CONTRACTOR is the best extension builder in Harwich. No obligation free ...
From £2,056
From Grandfather to Grandson, we have a combined experience of over 40 years within the construction industry providing a wide range of building se...
From £2,176
Greyline Interiors is a family run home refurbishment business with an eye for the latest trends and traditional values.We strive for quality, valu...
From £2,000
Trusted and professional extension builder in Harwich. Experienced in all extension buildering work and keeping within budget and on quote. James F...
From £2,312
San Diego Construction Custom Homes has experience building homes in the UK, Canada and the United States since 1999. It was founded on quality and...
From £1,496
Caley & Son are here to help customers who need an Extension Builder in Harwich. We offer a competitive rate to complete all your extension builder...

How much RSJs cost for supply and installation varies depending on the size, type and load-bearing properties, but in Harwich it ranges from £1,496 (Caley & Son based in IP3) to £2,344 (Edwin Lewis Dickinson Ltd based in CO12).
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 Harwich by posting a job with HaMuch and we will send it to extension builders in Harwich.
| Location in UK | Hourly Rate | Daily Rate |
|---|---|---|
| Install An RSJ near Harwich | £34 | £248 |
| Install An RSJ near Felixstowe | £31 | £231 |
| Install An RSJ near Tendring | £31 | £226 |
| Install An RSJ near Ipswich | £33 | £235 |
| Install An RSJ near Clacton-on-Sea | £31 | £232 |
| Install An RSJ near Colchester | £33 | £230 |
| Install An RSJ near Suffolk Coastal | £28 | £215 |
| Install An RSJ near Stowmarket | £30 | £221 |
| Install An RSJ near Sudbury | £34 | £229 |
| Install An RSJ near Maldon | £36 | £244 |
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 - £17,339

Two storey extension - £87,759

Build a timber frame extension - £25,839

Build a swimming pool - £80,839

Single storey extension - £51,784

Side return extension - £39,691

Install an RSJ - £2,039

Outbuilding - £9,839

Build a Mansard loft conversion - £51,839

Loft conversion - £32,243

Build a kitchen extension - £41,839

Hip to gable loft conversion - £41,839

Granny annexe - £86,839

Garden office - £9,839

Convert a Garage - £15,839

Garage - £18,339

Build a flat roof extension - £21,839

Build a dormer loft conversion - £41,839

Concrete foundations - £6,089

Convert a bungalow loft - £28,839

Convert a basement - £35,691