Many renovated buildings replace wood and masonry structural elements with steel. The replacement of heavy wooden roof and floor joists with the lighter steel open-web bar-truss joists is a common ...

DEAR TIM: I’m getting ready to build a large room addition that needs a beam to support the floor joists. I’ve been told that a wood beam will work, but I’ve always seen steel I-beams in other houses.

Q: Can you tell me a few things about the wood beam I uncovered while doing a plumbing repair? How is it possible for this beam to carry the load of everything above it? How do I know whether the beam ...