Best way to simulate Shade context material with a percentage of air-permeability?

Hi All,
I wonder if it is possible to simulate a material (a panel over a wall at a certain distance) with a specific percentage of air-permeability, or is better modelling a mesh? (this is for EP outdoor simulation - I have noticed MSHtoRAD component that is suitable for daylight analysis).

Here just an example:

I hope my question is clear enough. Thank you in advance for any tips.