We are having condensation problem in a closet on the ceiling. When checking out the attic for a problem we find that the floor of the attic in that area and the insulation is dry.


But in the bedroom area in the attic we find that where a large piece of plywood lays there is condensation on the under side of it and then the insulation is damp in that area from that.

But the closet are and on the attack stairs door there is condensation that forms large droplets of water.

What is the problem and how can we take care of this problem.

Thank you,
Paul Cox

The attic and closet may be 2 different problems. If there is excessive moisture in the closet, naturally it is going to condense on the ceiling. Could the moisture be coming from outerwear put away wet? Laundered clothing not fully dry? Make sure the insulation above it is in good shape too.

As for the attic, do you have a vapor barrier above the ceiling? I think when my house was built, there was a theory that ceiling vapor barriers caused more problems than good. If not, the easiest way to retro fit one is using a shellac based paint. I think Sherwin Williams sells one specifically for the purpose. It is a flat white and can be left as the finish coat.

The other thing is to meticulously seal all openings around wires and pipes. Not just the ceiling, but the basement or crawl space too. Moisture can follow things like the main sewer stack clear up to the attic. Caulk or foam all openings. Weather strip the attic door. Add ventilation to the attic.

You just can't let condensation create wet insulation.