Moisture passage through wall surfaces?
Moisture in wet air tries to flow toward dry air. This is due to “vapor pressure.” The flow acts independently of air currents. In winter, inside air is much more humid than colder outside air. So the vapor pressure, or equalization process, can actually force inside moisture through cement, wood, plaster and brick. Some varnishes and paints block the flow of the moisture, so condensation can occur between the inside and outside walls, or under exterior paint surfaces. This can cause rot in a home’s wood frame, blistering in paint, and deterioration of other building materials.
