What are purlins and closure strips?
Purlins are cross members running across the rafters of your structure. Closure strips match the corrugation pattern of the panels and are attached to the purlins. In light of the change from “CCA” treated wood to “ACQ” treated lumber should there be a more protective screw used with the installation of Suntuf? The new guide lines by the manufacturers of the ACQ lumber call for heavily galvanized or stainless steel due to the corrosive nature of the ACQ treatment. The change in the treated lumber chemical is a concern. Manufacturers of ACQ do recommend the use of either stainless steel or hot dipped galvanized fasteners (which Palram’s fasteners are not made from). That said, you have two basic options for using ACQ lumber: 1. Use a comparable fastener made from an ACQ approved material. Make sure that such a fastener uses either a neoprene or EPDM washer and that it is installed persuch a fastener uses either a neoprene or EPDM washer, and that it is installed per Palram’s recommendat
