Home › Universal Beams › 254 x 146 x 31

The standard beam for a 5 metre domestic opening, and one of the most requested sizes after the 203 x 133 x 25.

254 x 146 x 31 dimensions and weight

Approximate total weight by length — this is what determines how the beam is offloaded on site.

What is a 254 x 146 x 31 used for?

The 254 x 146 x 31 is the beam most often specified for the popular 5 metre span – the width of a typical rear elevation on a mid-size house once a wall has come out. Published domestic load tables consistently place it around the 5 metre mark under normal residential loading, and it is a routine specification for full-width knock-throughs, rear extension openings and loft conversions in larger properties. The 146mm flange gives it good lateral stability without the weight penalty of the heavier sections in the series, and at 251mm deep it is shallower than its serial size suggests, which occasionally helps in a constrained floor zone. At 31 kg per metre a 5 metre length is around 155kg, so mechanical offload is essential and access needs thinking about before delivery day rather than on it.

Indicative span

Under typical UK domestic loading, published load tables place the 254 x 146 x 31 in the region of 4.5m to 5.2m. That assumes a simply supported beam with an evenly distributed load, an imposed load of around 1.5 kN/m² and a dead load of 0.5–0.8 kN/m².

Grades, lengths and finishes

The 254 x 146 x 31 is normally supplied to BS EN 10025-2 in S275JR or S355JR. S355 is the higher strength grade and is increasingly the default across the supply network; if your calculations specify one grade, tell us, because the two are not interchangeable. Mill certificates can be supplied with the order on request.

Beams are supplied cut to your lengths rather than as standard mill lengths, and we can arrange:

• Cutting to size — supplied ready to install, no cutting on site
• Drilling, notching and holes to your engineer’s details
• Welded cleats, end plates and connections
• Painting and priming, including intumescent coatings
• Galvanising for external or exposed applications

Delivery

A 6m length of 254 x 146 x 31 weighs approximately 185kg. That is beyond safe manual handling, so plan for mechanical offload and a clear route to the opening. We deliver direct to site across London, the South and the Midlands, with HIAB lorry crane offload available on request. If access is restricted — a terraced street, a rear garden, limited headroom — tell us at quote stage rather than on the day, and we’ll plan the delivery around it.

Other sizes in the range

Also searched as: 254x146x31, 254 x 146 x 31 UB, UB 254x146x31, 254×146 UB31, 254×146 RSJ. The term “RSJ” is still widely used for universal beams, though strictly it refers to the older rolled steel joist section with tapered flanges.

• All universal beam sizes
• Universal columns (UC) — where the load is vertical rather than spanning
• RSJ beams
• PFC parallel flange channels

Common questions

Dimensional data shown is nominal and for guidance. Span figures are indicative and must not be used in place of structural calculations.