Have small roofed over back porch 10x16 and want to close it in with as much glass as possible, but not sure how to secure framing or block to the rock floor with out drilling. The rock is quite hard and aprox. 3"s thick. Currently the roof over is just supported by three 4X4's that just sit on top of the rock. Need to establish a more secure base if I intend to close it in. Just feel like drilling the rock is going to be a major job. Would setting one or two courses of block with just mortor be advisable. These walls could see 40 or 50 mph winds.