Steel BeamInstallers
Two installers seen from behind lifting a steel beam onto a padstone

RSJ installation · Derry City and Strabane

RSJ installation in Derry City and Strabane

RSJ installation across Derry City and Strabane, designed by a structural engineer and signed off by building control.

  • Free survey visit in Derry City and Strabane
  • Engineer's calculations arranged
  • Building control handled for you

Free survey in Derry City and Strabane

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  • Free survey visit
  • Engineer's calculations arranged
  • Building control handled
  • Fixed written price once scope is agreed
  • England, Wales, mainland Scotland & NI

Planning RSJ installation in Derry City and Strabane

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.

Across Derry City and Strabane, RSJ installation usually comes up when people want more light, a better layout or a way through to a new extension. We can survey in places such as Derry/Londonderry and Strabane and the villages around them. Whatever the reason, the beam is sized from calculations and the work is inspected before anything is covered.

Things to plan for

  • 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.
  • Sometimes two beams are bolted side by side with spacers, either to carry a thick wall or to fit through a tight space. Bolt spacing and spacer type come from the engineer's design rather than being decided on site.
  • If you already hold calculations from an architect or engineer, we install to those. Where something on site differs from the drawing, such as a weaker wall or a different joist direction, the engineer is asked to confirm before work carries on.
  • Where a long beam cannot be carried into a property in one piece, the engineer can design a bolted splice so it arrives in two or more lengths. The splice position and bolts are part of the calculations and must be installed exactly as drawn.
  • An RSJ inside a home commonly needs 30-minute fire resistance where it supports elements of structure. Fire-rated plasterboard boxing is the usual method, with intumescent paint used when the beam is to remain visible.

What happens, step by step

  1. Free visit

    A short visit to Derry City and Strabane to see the job, agree what you want and check the bearings, floors and services that affect the design.

  2. Calculations

    The engineer's calculations and a simple drawing are prepared for your opening and shared with you before anything is ordered.

  3. Building control

    A full plans application or building notice goes to Derry City and Strabane District Council under the Building Regulations (Northern Ireland) 2012 before work begins.

  4. Steel in, made good

    On site we prop, open up, fit and pack the steel, then fire protect, box in and plaster once the inspection is done.

Guide prices for RSJ installation in Derry City and Strabane

As a guide, budget £690–£2,150 per beam including VAT for rSJ supply and fit (single beam) in Derry City and Strabane, based on published UK cost guides adjusted for prices in Northern Ireland (-14%).

JobTypical guide rangeWhat it usually covers
RSJ supply and fit (single beam)£690–£2,150 per beamBeam supplied, delivered, lifted and packed on padstones, with propping (calculations and approval priced separately)
Temporary works and propping£130–£430Props, spreaders, needles and sole plates for a typical opening, installed and struck
Steel beam replacement£1,700–£4,750Propping, removing the failed beam, new steel on proper bearings, approval and making good
Fire protection to a steel beam£130–£520 per beamFire-rated board boxing or an intumescent coating system as specified

Figures include our approximate regional adjustment for prices in Northern Ireland (-14%) and are rounded. How these figures are worked out.

Building rules for Derry City and Strabane

In Northern Ireland, structural work comes under the Building Regulations (Northern Ireland) 2012 and is approved by the local council's building control. For Derry City and Strabane that is Derry City and Strabane District Council. We submit a full plans application or building notice before work starts and book the inspections.

The Party Wall etc. Act does not extend to Northern Ireland. Shared walls are dealt with under your title and the general law, so we recommend agreeing access and the work with your neighbour before it starts.

Building rules in Northern Ireland

RSJ installation by town

Questions about RSJ installation in Derry City and Strabane

Can you work on older or listed homes in Derry City and Strabane?

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.

What happens at the survey visit in Derry City and Strabane?

We look at the wall, the floor and ceiling either side and what sits above, measure the opening you want, and note cables, pipes and access for the steel. It usually takes under an hour and there is no charge.

What does RSJ stand for?

RSJ stands for rolled steel joist. It was the name for a hot-rolled I-shaped steel section with tapered flanges, and it is still used loosely for any steel beam in a house. Most steels fitted in homes today are universal beams, which do the same job with parallel flanges.

Is an RSJ the same as a steel beam?

In everyday use, yes. Builders and homeowners call most steel beams RSJs, whether they are universal beams, channels or columns. Technically an RSJ is one particular older section shape, but the engineer's drawing names the exact section type, so there is no confusion on site.

How is an RSJ installed?

The structure above is propped, the wall or opening is prepared, and padstones are bedded at each end. The beam is lifted onto them, bolted where needed and packed with shims and dry-pack. Props come out once it is carrying, building control inspects it, and the steel is then fire protected and finished.

How heavy is an RSJ and how is it lifted?

Weight varies widely with the section and length, from beams a small team can carry to steels needing mechanical lifting. The lift is planned at the survey, using enough people, trolleys and suitable lifting equipment so the beam goes up safely and level onto both bearings.

Who approves RSJ installation in Derry City and Strabane?

Structural work in Derry City and Strabane needs a full plans application or building notice to Derry City and Strabane District Council. We prepare and submit it with the structural engineer's calculations and arrange the inspections, so the completion paperwork follows the job.

Planning to take a wall out?

Book a free survey visit. You get an itemised written quote covering calculations, building control, steel and making good.