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203 x 133 UB25 Steel Beam RSJ – S355J0 Universal Beam & Rolled Steel Joist, Cut to Size to Any Length, Structural Lintel for Load-Bearing Walls

203 x 133 UB25 Steel Beam RSJ – S355J0 Universal Beam & Rolled Steel Joist, Cut to Size to Any Length, Structural Lintel for Load-Bearing Walls

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£75.95 GBP
£75.95 GBP
£75.95/m
(£63.29 ex VAT) Sale Sold out
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Cut-to-Size Calculator ✓ Free cutting
203 x 133 UB25 · cut to your exact length · delivered free
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Delivery in 5-10 working days
Estimated: Wed 29 Jul – Wed 5 Aug
Free UK mainland delivery Flat-bed lorry — customer offload
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Not sure what size you need? View our RSJ Beam Size Guide — span guidance, section comparisons and planning advice for all standard UK sections.

The 203 x 133 UB25 is an S355J0 structural steel universal beam (RSJ) weighing 25.1 kg per metre. Available in mill finish or red oxide primer, cut to your exact required length from 1m to 12m using our online cut-to-size calculator. With a wider 133mm flange than the 203 x 102, it offers greater lateral stability and is commonly specified for wide wall openings, rear extensions, floor and roof support and steel frames where this section has been confirmed by a structural engineer.

Steel Grade and Specification

Supplied in S355J0 structural steel conforming to BS EN 10025-2, with a minimum yield strength of 355 MPa. The section designation 203 x 133 UB25 refers to a nominal depth of 203.2mm, nominal flange width of 133.2mm and a linear mass of 25.1 kg/m. Full section properties are published under BS EN 10365:2017. See our steel grades and standards guide for more on S275 and S355.

Available Finishes

Mill finish is supplied as-rolled with natural mill scale — the standard untreated surface straight from manufacture. Suitable for internal structural use where a protective coating will be painted or applied on site.

Red oxide primer provides a shop-applied primer coat offering temporary corrosion protection during transport, storage and installation. Both finishes are structurally identical — the choice depends on your project specification and site requirements.

Cut to Size

Use our cut-to-size calculator above to enter your exact required length in mm. Steel is supplied in whole metres, so we add up everything you need and round the total up to the next full metre — two 4.2m cuts use 8.4m of steel and are billed as 9m, not 10m. The cutting itself is free of charge. Multiple cuts and quantities can be added in a single order, and all cuts are to +/- 3mm tolerance. Maximum single length is 12m. Cut-to-length steel is made to your specification and is non-returnable unless faulty or supplied incorrectly.

Section Dimensions

Depth (h): 203.2mm | Width (b): 133.2mm | Web thickness (s): 5.7mm | Flange thickness (t): 7.8mm | Root radius (r): 8.0mm | Depth between fillets (d): 171.6mm | Mass: 25.1 kg/m

203 × 133 UB25 — S355J0 Universal Beam 203.2mm depth, h 133.2mm · width, b 171.6mm between fillets, d 7.8mm flange, t r 8.0mm root radius 5.7mm web, s

Section Properties (to BS EN 10365)

Published section properties for the 203 x 133 x 25 UB. Figures are nominal and for reference only — your structural engineer will confirm the values used in design.

Property Axis y-y (major) Axis z-z (minor)
Second moment of area, I 2344 cm4 307.6 cm4
Radius of gyration, i 8.50 cm 3.00 cm
Elastic section modulus, Wel 230.7 cm3 46.2 cm3
Plastic section modulus, Wpl 258.2 cm3 71.0 cm3

Cross-sectional area: 32.0 cm2 | Surface area: 0.914 m2/m | Torsion constant, IT: 6.03 cm4 | Mass: 25.1 kg/m

Structural Engineer Notice

The 203 x 133 UB25 must be specified by a qualified structural engineer before ordering. Rackerman does not provide structural design advice and cannot confirm suitability for any specific opening, span or load condition. Building regulations approval is required for all structural alterations.

Delivery Information

Lead times are currently 5–10 working days. Delivery is kerbside only — our vehicles do not carry HIAB or lifting equipment. Suitable offloading labour or equipment must be arranged on site. Some postcode exclusions apply. See how our RSJ steel beams are delivered for full details.

Related Sections

Need a different size? Browse related universal beams:

FREQUENTLY ASKED QUESTIONS

What is a 203x133 UB25 steel beam used for?

The 203x133 UB25 is a Universal Beam (UB) weighing 25 kg per metre, used for spanning horizontal loads such as wall openings, lintels and floor supports. At 203mm deep with 133mm flanges, it is commonly specified for domestic extensions, loft conversions, wall removals and light commercial steelwork. It is supplied in S355J0 grade to BS EN 10025-2.

How much does a 203x133 UB25 weigh?

The UB25 weighs 25 kg per metre. A 3m length weighs 75 kg, a 5m length weighs 125 kg, and a 6m length weighs 150 kg. Factor in the beam weight when planning delivery access and lifting on site — beams over 4m typically need two people or mechanical lifting.

Can the 203x133 UB25 be cut to a specific length?

Yes. This beam is supplied cut to your required length from 1m to 10m using the calculator on the product page. Enter the length in mm and the price adjusts automatically. Cuts are to +/- 3mm tolerance. The beam is supplied in mill finish and red oxide.

What is the difference between mill finish and red oxide on the UB25?

Mill finish is the raw steel surface as it comes from the rolling mill — dark grey with mill scale. Red oxide primer is a protective coating applied over the steel to prevent surface rust during storage and transit. Mill finish suits jobs where the beam will be painted, fire-protected or enclosed. Red oxide gives temporary corrosion protection for exposed steelwork awaiting permanent coating.

What is the delivery time for the 203x133 UB25?

Steel beams are delivered on a flatbed lorry within 5-10 working days to mainland UK. The customer is responsible for offloading — beams of this size typically require two people or a forklift. Ensure site access is suitable for a full-size flatbed vehicle.

MONEY BACK GUARANTEE

Here at Rackerman, we take customer satisfaction very seriously. If you are unsatisfied with the quality of your product, please email us info@rackerman.co.uk or give us a call: 01665 497513 and we will make it right.

SHIPPING

It should take no longer than 1-2 business day to process your order, then 3-5 working days (5-10 working days on RSJs + Chippings) to then receive your order from us after dispatch.

If you haven't received your items in this time frame, please contact us.

RETURNS

If you are unsatisfied with your purchase, that's completely fine! We offer a 30 day money back guarantee to all customers, no questions asked! Please contact us to arrange a return.