The vapor barrier in a crawl space

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Vapor Barrier and What Does it do for your Crawl
Space

• A vapor barrier is a material that will block
  vapor diffusion from one side to the other. This
  means vapor cant get through, such as water
  vapor passing through the barrier on its way up
  and out of your crawl space.
• What is a vapor barrier used for?
• A vapor barrier stops water vapor from passing
  through it. In most cases, you will use a vapor
  barrier in places exposed to high humidity levels
  or in a place exposed to water.
• For example, if theres a lot of moisture in your
  crawl space due to ground saturation, you would
  need an effective vapor barrier that wont let
  water vapor pass . It is important that all sides
  of the vapor barrier are properly sealed. Be sure
  not to puncture any holes into the vapor barrier
  or any vapor will be able to pass through.
• What are the benefits of a vapor barrier?
• There is an easy answer to this question by
  using a vapor barrier, you will significantly
  decrease humidity levels in your crawl space.
  Less moisture means less mold and mildew growth,
  which can save you a lot of money that would
  otherwise have been spent on treatments and
  sprays that aim to remove mold and fungus.
  Therefore, a vapor barrier is definitely going to
  benefit your health as well as your wallet .

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• Its important to note that vapor barriers arent
  100 water proof no vapor barrier is.
  Therefore, they need ventilation as well. Without
  ventilation, the vapor barrier will cause higher
  humidity instead of preventing them (source
  Crawl Space Encapsulation Systems, vapor
  barriers). If you do not feel comfortable
  ventilating your vapor barrier, look for a
  comprehensive system such as the AirSpace Crawl
  Space System that includes ventilation.
• What is the downside of vapor barriers?
• The most common downsides include
• High cost vapor barriers arent cheap and
  they require professional installation. A vapor
  barrier also requires maintenance and care
  (moisture levels need to be monitored and if
  necessary adjusted with vents/fans). Without
  proper management, the moisture in your crawl
  space will not decrease but increase , leading to
  mold growth and high humidity. All of this may
  negate any benefits youd achieve with a vapor
  barrier in the first place .
• Not very aesthetically pleasing vapor
  barriers are usually thick and heavy, which makes
  them difficult to use in areas where you would
  like to keep the look of your house intact
  (living room, bedroom ceilings).
• Are vapor barriers safe?
• Yes. They can be safely installed without causing
  any health hazards in your crawl space. However ,
  vapor barriers should not be installed directly
  on top of items in a crawl space since they will
  block moisture but also block airflow . Remember
  that if water vapor is trapped under a vapor
  barrier with no way out it can lead to mold
  growth and high humidity levels.

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• The vapor barrier in a crawl space
• In most cases when installing a vapor barrier in
  your crawl space you will have two options
• Install the vapor barrier over the soil only
  (not on top of anything). This means the vapor
  barrier will be touching moist earth, which is
  fine as long as proper ventilation is provided.
• Install vapor barrier on top of crawl space
  items first and then cover it with plastic
  sheeting for vapor protection . However, this
  method requires more caution since you should not
  block any air vents or other openings that allow
  airflow into your crawl space.
• When installing vapor barriers in a crawl space,
  remember to check moisture levels regularly or
  hire someone who knows how to do this properly.
  With no management vapor barriers can cause high
  humidity levels instead of preventing them, which
  may negate all benefits you would achieve by
  using one in the first place. Vapor barrier
  installation is possible without professional
  help, however it requires time, patience and good
  understanding of vapor barriers. Since vapor
  barriers are not cheap , it is probably best to
  go with a company that specializes in vapor
  barrier installation . visit for Water Damage
  restoration

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• Thank You