Resisting Uplift
Thanks for the excellent article by Andrew DiGiammo on a simplified
method for framing a gambrel roof (September/October 2007). I am
wondering whether the detail could be simplified even further by
eliminating the steel strap across the ridge. It would seem that
the double plywood gusset across the rafters that meet at the ridge
acts to provide the same resistance to uplift as does the strap. If
the gusset is inadequate by itself, why not just make it slightly
larger, with enough fasteners to resist the uplift forces?
Carl Mezoff, PE
Stamford, Conn.
Clayton DeKorne responds: Thanks for the close read, and for paying
attention to the critical details. The point you are drawing
attention to reflects an oversight on my part. The label on the
illustration indicating the need for a metal strap should have been
suggested as an alternative uplift restraint for a gambrel frame
with a conventional ridge instead of the uppermost gusset. You are
correct that having both the strap and the gusset is redundant. The
revised illustration below includes the label as it should have
appeared initially.