A friend of mine is working on an architectonic project, where she designs a Faraday cage type of open space built in parks or other public places. The initial thought is to build it from some sort of metallic mesh (not metallic plates or foils), so the whole structure would be transparent for visible light, so the visitors would have some sort of feeling being outside, however without any mobile connection to the networks.
I have found the excellent answer by Rob Jeffries of the thickness needed for shielding the field by metallic shields, however I cannot find if the modulus of impedance $\eta$ would remain the same for metallic mesh (say hexagonal) made from the same material.
This problem raises several questions, such as how would one proceed with choosing the right materials and designing the structure? Would it be better to use one layer of mesh made from thicker wires or rather several layers of thin wire mesh? Typically at what orders of energy transmission cease the cellphones operate? Is the assumption, that sufficient diameter of the holes in the mesh is circa 1 cm, since it is safely smaller than $\lambda / 2$ for 3G networks (on the other hand the shielding in microwave ovens which utilize similar wavelengths seems to have holes cca 3 mm in diameter and is rather poor in terms of transparency / visibility).
Thank you for any helpful information!