Shims on columns

I saw the previous post and am not commenting on that one.

Just looking for a good resource or site for how to properly do it. In general it is common for wood shim’s to be used. I would prefer steel but all the homes have wood. I mention shims are prone to crushing, which is common in my area.

I’m interested how they should be set part. I always recommend if they don’t reach the full width it should be replaced with a shim going the full width of the girder. Any comments?

Thank you in advance. The attached photo’s are from a new construction I wrote up for not going the full width.

I agree should be full and not plywood

Good call. Shims should bear the full width of the girder/beam regardless of the material they are made from. Even the hardest woods like oak or hickory cannot compare to steel in shear or compression. When I served as a municipal building inspector I would only allow steel shims under residential girders. I do not know of a code that requires it, it is just a construction best practice.

I would recommend steel as well. It’s not a big deal to jack up the beam ever so slightly and pull the plywood out and put steel in.

Shims should also be secured to prevent them from translating.

That said, plywood is better than say a piece of monolythic wood because plywood is very strong, it resists splitting, the layers of plywood are oriented in such manner that the grains run in differing directions, it is dimensionally stable, etc. etc.

I’ve seen plywood used in timber railway bridges as shims between stringers and piles.