Steel Beams
RSJs, UB/UC sections, and bespoke plated beams - cut to length, fabricated in-house, and delivered to site or to your Rotherham pickup.
What we deliver.
Steel beams is the entry point to our structural work for self-builders, domestic contractors, and residential architects - RSJs for extension openings, UB and UC primary sections for loft conversions and knock-throughs, and bespoke plated beams where the structural engineer has sized something a standard catalogue doesn't stock.
We cut to length, drill, and weld end plates in our Rotherham workshop to your structural engineer's schedule. Fabricated to BS EN 1090 Execution Class 2, welded by coded welders to BS EN ISO 9606, UKCA-marked, and delivered to site on the day the bricklayers are ready. Same-day quotes on small domestic enquiries, 1-2 weeks on larger commercial orders.
What we make.
Every project follows the same certified workflow - so you get the same outcome whether we're making one beam or a thousand.
RSJs and standard sections
RSJs for extension openings and knock-throughs, UB and UC sections for primary structural, channel and angle for secondary, and hollow sections (CHS, SHS, RHS) for architectural and light-structural. Cut to length from mill-test-certified material, drilled and end-plated to the engineer's schedule, delivered ready to install.
Bespoke plated beams
Where a standard section won't span or won't take the loading, we fabricate bespoke welded plate beams to the engineer's design - flange widths, web depth, and stiffener positions all to the calculation. Welded by coded welders to BS EN ISO 9606 with weld procedure specifications for critical applications.
Engineer-led sizing, not catalogue fit
We don't size beams for you - your structural engineer owns the design, we own the fabrication to the design. Send the engineer's schedule with span, bearing length, loading, and any connection detail, and the beam arrives on your site on the day the bricklayers are ready. Clear liability split: engineer signs the calculation, we sign the fabrication.
Domestic through commercial scale
Self-builders needing a single RSJ for an extension, domestic contractors managing a loft conversion, commercial packages calling out secondary structural by the tonne - all through the same workshop, same quality gates, same UKCA documentation. Small domestic enquiries get same-day quotes.
Craftsmanship. Accountability. No shortcuts.
No subcontracted welders. No outsourced site crews. Every project from 3D model to final torque-check is handled by a certified UIS team from our Rotherham facility.
Tour our workshop Project & sample images.
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Four reasons we stay on your shortlist.
The same four reasons come up whether you're a tier-one contractor, architect or self-builder.
About UIS-
01
Accreditations & compliance
BS EN 1090 Execution Class 2. CHAS Elite, Alcumus SafeContractor, ISO 9001. Every project ships with a full QA pack.
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02
Experience & capabilities
Thirty years in business. Drawing board to torque-check happens in-house - no split accountability.
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03
People & values
CSCS operatives. Coded welders. Chartered draughtsmen. A family firm that treats your project like their own.
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04
Innovation & sustainability
Tekla 3D modelling. Automated welding cells. GRP composite solutions where steel isn't the right answer.
"As a self-builder of an innovative eco-home, I needed to partner with a company who offered competence, a willingness to push themselves and the resilience to stick with me during the challenging times. UIS built the metal structure of my property and added creative finishing touches - I trusted them to build a bespoke staircase, balcony and front gates for my house."
Questions clients ask us.
For structural beams, yes - we fabricate to the engineer's schedule rather than sizing the beam for you. Send the span, bearing lengths, loading, and any connection detail and we'll price the fabrication. If you don't have an engineer appointed, we can recommend one, but the calculation has to come from a qualified structural engineer for insurance and Building Control compliance.
Same-day on small domestic enquiries. From approved engineer's schedule to cut-drilled-delivered beam is typically 3-5 working days for a standard RSJ - faster if the section is in stock length, slightly longer for plated beams that need welding. We work to the brickwork programme.
Yes - every fabricated beam is UKCA-marked to BS EN 1090 Execution Class 2 under Factory Production Control. Mill test certificates with material traceability ship with the beam. The traceability pack is what Building Control and your structural engineer need for Part A sign-off.
Yes - our site team can install as well as supply, led by an SSSTS supervisor. We can handle Part A Building Control correspondence where the work falls inside our installation scope. Coordination with the bricklayers on programme, handover documentation, and 12-month defect liability through one named point of contact.
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