hello / I am going to build a garage / it will be all wood construction / most garages and houses here in the Shetland isles are of wood / the roof span will be 6.2m and will have a slope of 100mm / there will be a covering of 25mm marine ply. and on top of that profile sheeting / which is similar to corrugated sheeting / what size of beams should I use and with what centers / we do not get a lot of snow here and what we do get does not stay for long / thank you all /