Why are the weight loading calculations failing for my plain tile roof?

Weight loading calculations will often fail for plain tile roofs. This is because we use MCS default values for the tile weight, and the value for plain tiles is much higher than other roof coverings. If you are finding your calculations are failing when you don't expect them to, you can get a tile from the exact roof and measure the kg/m² to replace this value:

If the calculations are still failing, you will then need to consult a structural engineer.