Mass void doesn't cut component surface

[arch.rubens]

I've interesected two mass objects, one is form and one is void. Their are kind of complex & organic forms. The void is the one with blue line, but it works on the interior of the solid form, and doesn't cut the surface of the solid. The things is that on the solid one i want a a pattern -curtain wall. But the curtain wall covers the hole, and it means the surface is still solid even the void intersects it.

I've attatched a printscreen. (I've puted a pattern just on a half of building, but I hope you can see what i mean).

This is a better example. So how do I get rid of that surface? Thank you.

[maciejwypych]

Hi,

Cut your solid form with void first, before dividing the surface.