Hi guys.

I`m doing a simulation for a small structure and decided to go for wind simulation as well via flow simulation. The thing is, the structure is going to be fully covered by canvas and i`m not sure of the mechanical properties and maybe it going to be covered with something else. I tried to make a surface covered all the structure but the program asked me to define the thickness of it(shell). Please kindly advise the appropriate technique for me to solve this problem.

Thank you