Hi - I have an 18� x 20� backyard area that is grass and weed free, and completely flat, with a 2� slope over the 20� span. I would like to put some sort of cement or rubber tiles over this area. I have glued three 6 x 20' Polypropylene weed barriers, and this has been preventing weed growth. If I put down a one eighth inch layer of sand, could I use your tiles on top of the weed barrier for walking, to put tables and to use to move loaded wheelbarrows, etc.?