We have two fake dormers on our house. We planted them directly on the wood that covered the roof trusses. However, before we put them on we made sure the black paper the roofers used was also placed under the dormers so it would appear black inside. On top of that, when we had our windows made, we had them put privacy glass on the inside panes of the windows but made sure the exterior panes were not privacy glass. It helped so that people couldn't actually see directly in, but it didn't look like a true privacy glass window either. Plus the privacy glass well help the window from looking too dusty.
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false dormer window idea
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