Vapor Barrier – More Information
Vapor Barriers – Controlling Water/Moisture In Your Crawlspace
Moisture and water in crawlspaces and homes cause mold, fungi, and wood rot. These eventually cause structural damage to your house, contribute to respiratory/health problems for your family and promote insect activity. About one-half of the air in your home comes from your crawlspaces.
Traditional vapor barriers consisted of sheets of plastic laid down on the ground to stop the water from the ground from becoming water vapor in the air and be absorbed into the wood members of construction and the home in general.
When the area around your home is wet moisture will “wick” or leak into the ground in the lower crawlspace. When the water vaporizes out of the ground under the barrier, it will turn back into water and go back into the ground until the surrounding outside areas and air dry out.
However, if the ground or air don’t dry out the moisture increases. That is why vapor barriers should be combined with other methods of moisture remediation to create a more permanent solution.
Another problem with older vapor barriers is that they can be easily torn and/or moved and lose their seal when workers crawl into your crawlspace to make repairs or bring in new materials, add new systems, construction, or fix plumbing, HVAC or electrical, etc.
For these reasons thicker, tougher vapor barriers have been developed consisting of a fiber infused plastic barrier that is 12-20 millimeters thick and much stronger and harder to tear than plastic alone. These membranes are also taped at the seams and staked to the ground for greater effectiveness and longevity. They can also be placed vertically on walls and support piers to create a true waterproof wall and floor barrier.
If there is water intrusion, however, this needs to be used in conjunction with French drains or other forms of water removal so that water is not “trapped” between the barrier and the foundation which could result in foundation deterioration or failure.
You need to have a professional inspect your home to create a fully permanent, ongoing moisture remediation program.