Damp-proof paints, as the name suggests, are designed to protect both the exterior and interior walls of your home from dampness. These paints contain plastic components that act as a barrier, guarding your walls against moisture, humidity, and water vapor. However, over time, the use of exterior damp-proof paint can have adverse effects on your home. While they effectively shield your walls from heavy rainfall, they can also trap moisture within the walls, preventing it from dissipating into the surrounding environment.