Our 18mm fascia boards are made from high quality PVC.Available in sizes from 150mm to 250mm, plastic fascia boards should be fixed using 2 x 65mm polytop nails at each rafter (maximum spacing 600mm for white and 400mm for all other colours).The return leg on the board is slightly rebated to accept a soffit board. The return leg measures 40mm overall from front to back as can be seen in the technical drawing tab.