i'm using reclaimed rosemary clay tiles and possibly need to have the roof pitch lower than the 35 degree required. Its a lean-to over the kitchen 4m long x 2.5m wide. Not too sure about angle but probably anywhere from 25-35 degree. Can i use 12mm marine ply + bitumen type felt + lath + rosemarys? If so is there an alternative to nailing the lath over the ply/felt? A velux window will also be added
