Q. Ideally, pier/beam connections are always properly aligned, with the pier at the right elevation to fully support the beam above. But in the real world, a little shimming always seems to be required. Are shims ripped from framing lumber really adequate for supporting beams, or should I use plywood?
A. Tim Garrison, a professional engineer, the president of ConstructionCalc.com, and the author of Cracks, Sags, and Dimwits: Lessons to Build On, responds: Wood achieves its greatest compressive strength when it's oriented like a post, so that loads are applied parallel to grain and resisted by its long fibers.
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