Abstract: A grease absorption curb system for use in conjunction with roof top cooking exhaust fans to prevent grease which accumulates around restaurant exhaust fans from degrading roof top materials. The curb comprises a plurality of durable, lightweight, non-biodegradable blocks which are releasably joined together by a tongue and groove system to define a perimeter curb around the exhaust fan, with at least some of the blocks having drain tubes to allow water to drain from within the perimeter curb system to outside of the curb system.