fig1 from the flashing strip which is approximately 3 u2033 wide to cover the ventilation slot in the sheathing the opening height of approximately 1 u215b u2033 would provide adequate ventilation and still be low enough to not interfere with the tile element 31 is shown designed with three vertical fingers pointing upward and connected at the base having a flat plane at the bottom and the top of the fingers creating a flat plane the material must be rigid enough to hold the leading edge of tile 20 approximately one inch above the preceeding tile creating a gap between both tiles to allow the flow of air the material must also be flexible enough for the base to follow the shape and contour of the preceeding tile as it will be bonded to both the bottom and top tiles with an adhesive roof tiles are supplied by many manufacturers all having different sizes and shapes which requires the afore mentioned flexibility the most common shapes are flat u201c w u201d and u201c s u201d the color and any visual characteristics are unimportant as the riser is under the top tile and will not be visible tiles have stiffener ribs on both the top and.