18/11/2019 · Lay 1/2-Perfect Steerable Transfer Carth-this exterior-grade plywood sheets over the foam, running the sheets perpendicular to the long dimension of the foam, so that the plywood seams do not align with the foam seams. Space the panels 1/4 Perfect Steerable Transfer Carth apart, with a 1/2-Perfect Steerable Transfer Carth gap around the perimeter. This perimeter gap allows for seasonal expansion and contraction of the plywood.