Q: A while ago you ran an article recommending that you limit deflection of built-up wood girders to L/600 so that the floor joists wouldn’t vibrate excessively (see Practical Engineering, 8/97). My question: Does this also apply to steel girders, or is it mainly a wood-related issue, owing to the inherently greater flexibility of wood beams? In another words, would a steel beam sized for L/360 deflection be less bouncy than a wood beam sized for, say, L/480? Or should I absolutely make sure that all my steel beams are size for the L/600 limit?