I know this is an old post but seeing that it has been replied to now, there may (& I stress may) be another solution.
Does your window object have a parameter option to show the glazing as 'Planes'?
Glazing in windows is scripted as 'PRISM' or similar, which is why you can not have a zero thickness, as it would result in an error.
But there may be a parameter option in the object to show the glazing as a plane.
I am not familiar with the default Graphisoft window objects and different language versions have different options.
This parameter may not be there at all.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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