The list of problems that moisture can cause in your home is very long and troubling. Part of the issue is that detecting a leak can be very difficult, and even when it is detected, tracing the water back to its source might take a lot of detective work. On thing that protects your home from moisture is a vapor barrier. Depending on the application, there are different types of barriers you can use. They can be in the form of a polyethylene plastic sheet, paper, and even a paint. Depending on the type used, the application process is different. From a cost perspective, using paint is the cheapest and easiest method, especially if it is a surface that you were planning on painting already. It is, however, important that the paint covers the area well, and that damage to the paint is repaired as soon as possible.
If installing a plastic barrier, it is important to be careful not to rip it. Depending on the type you use, you might be able to get a damage resistant barrier that doesn’t rip as easily.