My Beam Sits on an RHS Lintel, Not a Padstone — Is That OK?

Yes, provided the RHS lintel was itself specified by PorthouseDean as part of the structural design. The standard padstone detail is for beam ends bearing onto masonry. Where the supporting element is a steel lintel rather than masonry, a different detail applies.

When This Situation Arises

This occurs when a secondary beam (e.g. across an opening) must bear not onto the masonry blockwork wall but onto a steel RHS lintel that is already carrying the masonry above. On some projects, the sequence of construction means that by the time the secondary beam is installed, the padstone position has been taken by the RHS.

If the drawings showed a padstone at that position but the as-built condition has the beam sitting on a PorthouseDean-specified RHS instead, the padstone requirement can be replaced with a direct bearing detail for the beam-to-beam interface.

What the Correct Detail Involves

The beam end bearing on the RHS lintel uses a direct steel-to-steel contact. The key requirements are:

– The beam must be centred on the RHS to avoid eccentric loading
– The beam must have full end bearing — it must bear over the full width of the RHS top flange, not just the edge
– The joint must be positively fixed (bolted) to prevent the beam from lifting or shifting

If the connection involves transferring significant shear from the secondary beam into the RHS, this may need to be checked by the engineer — contact PorthouseDean with the beam references and the load scenario if you are unsure.

What to Do on Site

If you have reached this situation, contact PorthouseDean before proceeding. We will confirm whether the beam-to-RHS bearing is within the scope of the original design or whether a brief change request is needed. In most cases this is a quick review.

Do not bolt or weld the connection using arbitrary dimensions that are not from the engineer’s documents — the plate thickness, bolt size and spacing are structural parameters.

Contact PorthouseDean with your beam references and we will advise.