Panels are engineered for winds of 135 mph, so if we have that we will have other worries. Also sheathing doesn't come in to play as the racking is mounted into the rafters. Yes, older homes that have true wood and set 24" OC may need some structural support (knee wall). Yes subsidies are needed, just wish we weren't phasing them out as Big Oil still is subsidized by the 10's of billions.