When the ultimate protection of your Sika Sarnafil roof membrane is required, look no further than the LightGUARD or HeavyGUARD products. Perfect for protecting the membrane from severe weather such as hail, LightGUARD/HeavyGUARD is a composite modified concrete top layer bonded to extruded polystyrene insulation. The LightGUARD/HeavyGUARD board is installed directly on the separator sheet over the completed Sika Sarnafil roof system making the membrane completely protected from hail or roof top traffic. Both LightGUARD and HeavyGUARD come with a 2"-3" thick polystyrene insulation board. LightGUARD then has a 3/8" thick composite concrete layer while HeavyGUARD has a 15/16" thick composite concrete layer.