Crawlspace Encapsulation

The Problem with Vented Crawlspaces

Crawlspaces were never intended to provide air to the living space. They were a cost effective way to provide a foundation on which to build a house at a time when construction materials and practices were very different from those available today. Today's airtight construction requires that crawlspaces be improved to correct the unintended consequences that our focus on energy efficiency has had on houses with vented crawlspaces.

The Solution – Encapsulate your Crawlspace

Simply put, close the crawlspace and then clean and dry the air in it. By closing the crawlspace - sealing the walls and dirt floor of the crawlspace - moisture from the primary sources (outside air and the earth underneath) is reduced. Encapsulating the crawlspace also reduces the amount of unconditioned outside air introduced into the conditioned living space, reducing energy costs. By dehumidifying and filtering the air in the crawlspace clean dry air is supplied to the living space when the house draws make-up air from the crawlspace. Dry air is less expensive to heat and cool further reducing energy costs. Dry crawlspaces are less subject to rot, mold growth, and insect infestations thus protecting your investment and improving air quality in your home. Encapsulating your crawlspace turns dirt to diamonds.

Why Encapsulating Your Crawlspace Makes Sense

  • It reduces your energy bill.
    Encapsulation of vented crawlspaces reduces heating and cooling costs by 15 - 18%

  • It protects your investment.
    By reducing moisture levels the likelihood of insect damage and rot in your home decreases.

  • It helps to create a more healthy environment for you and your family.
    By reducing allergens such as mold spores and dust mite feces in your home, you will enjoy a healthier living space.


Energy Efficient Houses "Breathe" Differently

While living spaces were being more tightly sealed, crawlspace construction remained the same. Air began to flow through the houses differently. By tightening up the living envelope, the house is forced to pull replacement air out of the crawlspace. Make-up air is now drawn from the crawlspace below into the living space above. In turn, air is drawn from outside the house into the crawlspace.

This creates three problems:

Find Your Local Branch

What we do:

  • Clean up
    Remove broken blocks, stones, and other debris.
    Remove all cellulose materials (cardboard, wood scraps, etc.)

  • Seal up
    Seal foundation vents.
    Seal other wall penetrations.
    Seal gaps. Seal crawlspace door.

  • Cover Up
    Cover walls and piers with 12 mil membrane.
    Cover crawlspace floor with 20 mil membrane.
    Joints are lapped and taped.

  • Dry Up
    Install a commercial grade dehumidifier.
    Install water drainage and sump pumps if necessary.
    Install a remote humidity monitoring system.

  • Follow up
    Supervisor visit and walk through upon job completion.
    Regular service to:
       Inspect and repair membranes and sealing.
      Take wood moisture readings.
      Take humidity readings in the crawlspace.
      Remote data collection using a humidity and temperature data logger.
      Quarterly or semi-annual service - your choice.