Building Consultant
One of the biggest benefits of open cell foam is that it expands so much after it has been applied, meaning it can insulate hard to reach nooks and crannies in a home. These types of areas can be hard to insulate with closed cell foam. Open cell foam is excellent for soundproofing where a single application can completely fill the area between studs.
If the crack is in your ceiling hot air in the attic can draw/suck cold conditioned air out. It happens through a natural principle of science call convection.
I’ve lost count of the number of homes I’ve inspected that have folding stairway built into the hallway or laundry room ceiling. More often than not the folding legs are not trimmed to the correct length or properly secured to the framing.