Can I install the pre-cut turf roll or playground turf over a regular hot torched rolled roof that has a little slope for drainage? I was thinking about putting a 3/4 padding underneath to add some strength for traffic and durability for patio furniture. We are in South West Virginia so, it rains, and it gets hot. Is this a good product? How long will it last on a southern exposure area 40 ft up in the sky? My house is partly underneath. Thanks!