When I get to putting the extension flat roof together, it will have 140mm Celotex onto of the timbers/firrings, the 18mm OSB board and I was wondering if the are decent screws on the market say 170mm long to hold this lot together?
Longest I can find at screwfix are 160mm and these are £45 for 50 of them. My roof is 7m x 4m so £45 worth isnt going to go far
Longest I can find at screwfix are 160mm and these are £45 for 50 of them. My roof is 7m x 4m so £45 worth isnt going to go far