RSJ installation · Dorset
RSJ installation in Dorset
RSJ installation across Dorset, designed by a structural engineer and signed off by building control.
- Itemised written quote
- Beam sized by a structural engineer
- Covering Dorset and nearby
- Free survey visit
- Engineer's calculations arranged
- Building control handled
- Fixed written price once scope is agreed
- England, Wales, mainland Scotland & NI
RSJ installation in Dorset: how it works
RSJ installation is the supply and fitting of a structural steel beam to carry load across an opening or in place of a wall. RSJ stands for rolled steel joist, an older name for an I-shaped steel section; most domestic beams today are universal beams. Installation covers fabrication to the engineer's design, delivery, lifting, bedding on padstones and packing tight.
If you are planning RSJ installation in Dorset, the order of work matters as much as the steel: survey, calculations, approval, propping, installation, inspection and making good. Towns we cover include Christchurch, Weymouth and Bournemouth, among other places in the area. We run that sequence for you as one job with one point of contact.
Things to plan for
- Heavy steels are raised with suitable lifting equipment rather than by hand alone. Manual handling is planned so nobody carries more than is safe, and the lift is coordinated so the beam goes up level onto both bearings together.
- Delivery can make or break an RSJ job. A long beam has to turn through a front door, along a hallway and past the stairs, so routes are measured at the survey and alternatives such as a window opening are planned early.
- The engineer chooses the section type for the job. Universal beams suit most spans, universal columns are stockier and used as posts or where depth is limited, parallel flange channels fit against walls or timbers, and box sections suit slim or exposed members.
- Structural steel comes in recognised grades, and the engineer's drawing states which grade the calculations assume. The steel supplied matches that specification, and the delivery paperwork is kept so building control can see what has been fitted.
- RSJ originally meant a rolled steel joist with tapered flanges. Most beams supplied for homes today are universal beams with parallel flanges, but the term RSJ has stuck, and builders, engineers and building control all understand what it means.
What happens, step by step
Survey in Dorset
We visit, look at the wall and what sits above it, measure the opening and note services, access and how the steel can be brought in.
Engineer's design
A structural engineer sizes the beam, padstones and any posts, and sets out the temporary support needed while the wall is out.
Building control
We submit a building notice or full plans application to the local council's building control team, so approval is in place before the wall is touched.
Install and sign-off
Props go in, the opening is formed, the steel is set and packed, building control inspects it, and we make good.
How much should I budget in Dorset?
As a guide, budget £820–£2,580 per beam including VAT for rSJ supply and fit (single beam) in Dorset, based on published UK cost guides adjusted for prices in the South West (+3%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| RSJ supply and fit (single beam) | £820–£2,580 per beam | Beam supplied, delivered, lifted and packed on padstones, with propping (calculations and approval priced separately) |
| Load-bearing wall removal with steel beam | £2,050–£5,150 | Typical internal wall up to about 4 m: calculations, building control, propping, steel, padstones, fitting, fire protection and making good |
| Structural calculations for a beam | £260–£770 | Site measure or photos, beam and padstone design and calculations for building control |
| Temporary works and propping | £150–£520 | Props, spreaders, needles and sole plates for a typical opening, installed and struck |
Figures include our approximate regional adjustment for prices in the South West (+3%) and are rounded. How these figures are worked out.
Building rules for Dorset
Structural openings in English homes need building regulations approval before work starts. The local council's building control team can deal with it, or you can use a registered building control approver. Either way the steel is inspected before it is covered, and a completion certificate is issued at the end. Keep it safe for when you sell.
Terraced and semi-detached homes often need party wall notices, because cutting into a shared wall to take a beam end is notifiable under the Party Wall etc. Act 1996. Allow at least two months for the notice period unless your neighbour agrees sooner.
RSJ installation by town
RSJ installation in Dorset: your questions
Can you work on older or listed homes in Dorset?
Yes. Older homes often have lime mortar, timber lintels or shallow footings, which the engineer allows for. Listed buildings need listed building consent for internal structural changes as well as building regulations approval, and that must be in place first.
Can I stay at home while the work is done in Dorset?
Usually, yes. The work area is screened and floors are protected. The rooms either side of the opening are out of action for a few days, and there is some noise and dust while the masonry comes out.
Do I need building regulations approval to fit an RSJ?
Yes, when the RSJ carries structural load such as a wall, floor or roof. In England and Wales building control is notified or approved beforehand, Northern Ireland needs a council application before work starts, and Scotland requires a building warrant first. A completion certificate confirms sign-off at the end.
What is included in an RSJ supply and fit price?
Our itemised written quote sets out the calculations, building control, steel and fabrication, delivery, lifting, padstones, propping, labour, fire protection and making good as separate lines. Once the specification and scope are agreed, the price is fixed in writing, so you know the full cost before work starts.
Can an RSJ be delivered in sections?
Yes, where access is tight. The engineer can design bolted splice joints so a long beam arrives in two or more pieces and is joined in place. The splice has to be part of the calculations from the start, because it changes how the beam carries load at that point.
Does an RSJ need to be painted or boxed in?
Usually it needs fire protection, most often by boxing in with fire-rated plasterboard and skimming. If you want the steel on show, an intumescent paint system can be applied to the specified thickness and then top-coated in your chosen colour. The fabrication primer is not fire protection on its own.