Generally, as per timber tables, floor live loadings are taken as 1.5kN/m2. I don't know if it was a typo, but 2kN/m2 is approx 200kg/m2 not 2000! There are 9.8N per kg. As for roof loads, I used 0.9kN/m2 dead load and 0.75kN/m2 Live load (in plan) for a 45degree pitched clay tiled roof in the south...
