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Other stories by Scott McVicker

  • Q&A: Purpose of T&G Plywood

    Q: Does tongue-and-groove plywood add extra strength or stiffness to a floor system, or does it just help prevent floor squeaks?

  • Q&A: Splices in Built-Up Beams

    Q: Is it necessary to place splices in built-up lumber beams directly above the support posts?

  • Q&A: Strength of PT Lumber

    Q: Does CCA pressure treatment adversely affect the strength or durability of framing lumber?

  • Q&A: Weight of Steel vs. Lumber Beams

    Q: For the same loads, which is heavier, structural steel beams or lumber beams?

  • Q&A: Rafter Thrust in a Shed Roof

    Q: Does a cathedral shed roof addition need collar ties to restrain the outward thrust of the rafters?

  • Q&A: Shear Strength of Gypboard

    Q: I’ve heard that engineers give no structural "credit" to gypboard, but I know it greatly stiffens partitions when I nail it up. How much shear strength does drywall really have, and why not credit it in the design?

  • Q&A: When Are Collar Ties Needed?

    Q: Collar ties don’t seem necessary in attics where the rafters come all the way down to the ceiling joists. Can you remove some of them to create headroom?

  • Calculating Loads on Sloped Roofs

    Q: I often see roof loads calculated based on the horizontal run of the roof. But isn’t it more accurate to figure the weight of snow and roofing materials by measuring along the actual length of the rafter? Thus, as the roof gets steeper, the rafter gets longer, and the weight of roofing materials...

  • Q&A: Safety Factor in Wood Construction

    Q: Doesn’t the safety factor in wood construction mean that most wood structures are way overbuilt?

  • Q&A: Using Purlins & Struts To Reduce Rafter Spans

    Q: Does using purlins and struts at midspan allow you to cut the roof span in half compared with what’s given in a rafter table?