Are there any special framing or structure considerations for slate?
A good solid deck with 16″ on center framing is preferred. Most structures are built to handle wind and snow loads that far exceed the weight of slate. However, a weak structure that has too much flex to it will result in a poorly installed slate roof. Ideally, one would use a 3⁄4″ thick tongue and groove deck on 2″ x 12″ rafters 16″ on center. However, this is an expensive deck, and would be a rare sight today. Otherwise, it would be best to have at least 5/8″ plywood or 3⁄4″ plywood over 16″ on center trusses built to handle slate.
