Do you have vapor barriers in your home? If you don’t know, you shouldn’t feel bad. It is not something that most of us think about regularly. The purpose of a vapor barrier is to keep moisture out of your home. It can consist of a polyethylene plastic sheet, paper sheets or even a paint. While the sheets are fastened to your walls, a paint can be very useful, especially if it is being applied to a wall that you were planning on painting anyway.
The sheets are very easily ripped when installing them, which is why there are thicker and sturdier varieties, but they also cost more. Usually, you will invest in that type of vapor barrier when you need to install it on a rough uneven surface.
Any damage to the vapor barrier is going to be a problem since it will negate the purpose of the whole sheet. This is the same case when using it in paint form. If you scratch off the paint in an area for some reason, you need to re-apply the paint.