Girder end bearing

I had a new house today that had a steel “I” beam resting in a pocket on a poured concrete foundation wall. I could not verifiy 3" of bearing or ventilation as builder sealed the opening with mortar.

My question: Is there supposed to be 1/2" ventilation around steel or wood girder end bearings?
I can not find the 1/2" Vetilation anywhere in the06’ IRC.
Am i correct in that thought?
I recall reading that somewhere.

Thank you

I don’t really see anything wrong here, but most likely over the years, the mortar will crack and might spall off due to the expansion and contraction of the steel. Since the beam has a primer on it, it should not be a problem.

The biggest thing would be bearing, but then you can’t inspect it so note it as such.

Marcel :slight_smile:

One would have to know the design load carried by the girder in order to know what amount of bearing was required, and one would also have to know whether a bearing plate sufficient to transfer the load to the concrete was provided. Since these items cannot be verified, do what Marcel said.

Thank you, I did note that verbally and in the report that it was not able to be inspected.
The question I have now is, are end-bearing beams required to have 1/2" space around bearing pocket for ventilation.
Any comments
Thank you again.


No, Steel beams do not require air gaps at the bearing end. That steel beam install is fine.

“Click to Enlarge”

Wood beams do require air gaps due to rotting.

“Click to Enlarge”

If the cavity is too big, I always recommend wedging in this pocket to prevent twisting of the beam.

Typically, the beams wood or steel are always left open, and insulated later if the basement gets finished.
Some foundation contractors use something like this to create the beam pocket.

Beam Pocket

The Beam Pocket is a reusable tapered steel boxout that leaves a void pocket at the top of the foundation wall for steel or wooden beams. The standard 6 x 8 x 4 deep size comes with a handle for easy carrying and removal.


Thank you for the clarification Marcel and David.
I appreciate your help.
The buyers father is a contractor and we both had the thinking that even steel beams needed a small gap for venting.

David, who’s did the illustrations are those? Carson Dunlap?


wedging with wood can allow the moisture in the concrete to leach into the wood wedge and the beam. wood needs to be isolated from concrete (or be pressure treated) so the wood beam should have something to isolate the wood from the concrete - like a pice of 30# felt.

as far as twising goes, solid blocking or bridging is used to prevent twisting of beams and joists.

Wedging with block or 2X4 is what I was referring to. How’s someone going to find an angle at that location.

So you’re telling me that if you see a wood beam with no felt protection, you’re going to write that up?

Give me a break…

I think he must have seen fig. 16 on this link.

Typically, framers around here leave the pocket a little lower than the size of the beam to be installed and latter install pressure treated lumber to the proper elevation.

This little felt game is a little to much expected for builders to even think about.

And yes to ventilation, because I never see any of these beams pockets filled in and if I would, it would be called out as unable to verify bearing and potential to wood rot due to moisture being wicked in and the condensation on the end of the beam suseptable due being so close to the exterior extremities of the foundation face exterior.

How’s that Dave? will that help them? ha. ha.

Marcel :slight_smile: :wink:

Here’s one with plenty of air flow. Friday’s inspection.

steel girders can be grouted. The grouting will cause (eventually) rusting of the beam end, but not for a Looong time.

Wood beams should be ventilated.