What's A Vapor Barrier And Why You Need One?

If you happened to look outside your window today, you probably noticed that the rain has returned to us.  We are used to this in the Seattle area, but it was nice to have it gone for a little while at least.  Of course you don't really need me to tell you that we live in a wet area of the country, but what you may need to hear is how all this moisture affects your home.  Water is the enemy of your home.  In fact, your entire home was built and designed to repel water.  You can look up and see the slope of your roof, gutters and siding and see how rain water is moved off of the house, what you don't see is how your water deals with water below your home.

What Is A Vapor Barrier?
A vapor barrier is simply a plastic sheathing that rests on top of the soil underneath your home.  Its purpose is to stop the wet, damp soil from releasing water vapors that rise up and infect the wood underbelly of your home.  By limiting the amount of moisture that can rise into the subfloor, it also cuts down on mold and fungus from forming.

Do I Already Have One?
Probably.  If your home is a newer home, then you should have a vapor barrier that is installed to code.  However, older homes sometimes do not have one and even if they do have one, it may not be up to code.  Currently, the code is to have black (not clear) plastic that is at least 6 mil.

How Do I Get One?
There are a few different ways to go about this.  First (and I recommend this) you can call and have Healthy Homes install one for you.  But, if you are the do-it-yourself type, you can probably roll up your sleeves and do it yourself.  If you do elect to go this route, you should by almost twice as much plastic as you think you will need.  For example, if you have a 1000 square foot home, you should by about 1500 square feet of 6 mil black plastic.  There is nothing scientific to installing it, but you do want to be sure to overlap your seams by 6-12 inches.  It gets tricky around the pier posts, but just cut slits and overlap the plastic. 

If this sounds like too much work (and it really is tough, dirty work) you can give us a call.  It might not cost you as much as you might think to have one installed for you and it can save you money later on by avoiding water damage to your crawl space.