I livery in an old apartment building with neighbors who smoke. I am pretty confident that I have found where the smoke is getting into my apartment:a recessed closet that shared a very thin wall with a matching closet in their apartment. There are thin gaps along the top and bottom of this thin wall.
I have some silicone based caulk laying around and it matches the color of the closet. Is this an appropriate sealant for keeping smoke out?