Can Rhino extract only exterior surfaces of the model ignoring all of the inside geometry?

I need to find out the way to lighten model as much as possible ans have only outer faces of it. When I try to achieve it through boolean, it makes a negative copy of the volume with all of the inner geometry. Is there a way to make something like a plaster mold, so Rhino would read a model as a whole solid or ignore insides?

What about the windows and doors? You still want those features?

I need every surface visible from outside, i.e. front side of exterior door (not the inner side)