About Vapor Barriers

• Even though the name implies that vapor barriers block all water vapor, some still seeps through the material. What these barriers do is help to prevent as much water from permeating through and reaching your insulation. By installing a vapor barrier before insulating your basement, you get an extra measure of protection against damaging moisture.
  
  Barriers sold at local home improvement have rates, called perms, which is a measure of how well it prevents water vapor permeation. Any type of barrier with a perm rating of less than one is sufficient for protection against water vapor in your basement.
  
  

Vapor Barrier Benefits

• When water vapors penetrate, it forms condensation in between the walls. Over time, this moisture breeds bacterial and fungal growth in the form of mold and mildew. Without a vapor barrier, the mold and mildew growing on between your walls, reaches the inner wall. When this happens, the only way to fix the problem is to tear down the existing walls and put up new ones. According to the United States Environmental Protection Agency (EPA) and the Centers for Disease Control (CDC), one of the best ways to help deter the proliferation of mold and mildew growth is to install a continuous vapor barrier.
  
  Another good reason why you should use a vapor barrier before insulting your basement is that if you don't and condensation forms, it makes the insulation wet. When it becomes wet, its properties dramatically weaken. This leads to heating and cooling energy loss and higher electric bills.
  
  Aside from the heating and cooling energy loss and higher electric bills, if insulation becomes wet and has contact with your framing studs on your basement walls, it eventually leads to the wood rotting. If the wood on the framing studs rot, it will no longer be able to support the weight of the walls and you will have to tear the walls down and rebuild them from studs.