Formwork area of any element (areas in contact subtract problem)

Hello, I am doing a script to calculate all the areas of elements by orientation, put this value in a project parameter created to after in naviswork i can do quantification with this parameter easily.

I already did almost the entire work but I am having problem because is counting the areas of elements that are in conctact each other, to formworks and others services of quantification this is not ideal.

I have tried substract the surface using geometry intersect and worked sometimes (like in photo) whem i use with few elements but to a bigger project doesnt work. (blue group)

Please someone help to end it and maybe do with less nodes.

formas.dyn (167.8 KB) PACOTES