Perhaps more important than insulation, is a tight air/vapor barrier installed to create a sealed envelope around the exterior of your building. According to the Minnesota Dept. of Commerce, air leakage can account for one third of the total heat loss in an average home. Warm air leaks out and cold air leaks in. Along with the air, moisture (vapor) escapes and can condense inside the walls or attic which could cause serious structural damage when mold, mildew and rot occur.

What to do?

When adding on or building new, you can use state of the art products to create an air/vapor barrier envelope. A continuous air/vapor barrier is essential to keep moisture from entering insulated cavities where it can condense into water. A full coverage vapor retarder inhibits vapor diffusion and keeps the insulation and structural cavities dry, therefore maintaining stated R-values and structural integrity.

• Studies show that 10 gallons or more of water per day can evaporate into a house from the basement!

Conservation Technologies carries the following products to create such a barrier:

In an existing home caulking and weather-stripping are the answer. There are many resources available through libraries and state departments of public service. The MN Dept. of Commerce has free booklets available on a number of topics related to making your home energy efficient.

TUFF 3 is a cross-laminated barrier made of virgin resin polyurethane making it a light weight, durable barrier of outstanding strength. It is UV stabilized and pinhole free. White color.

• TIP: At the framing stage place a strip of one of these vapor barriers behind the framing where the interior walls meet exterior walls to ensure a continuous vapor barrier.

TUFF 4 is a two-ply, cross laminated, UV stabilized, high density polyethylene. It resists tearing and punctures like no other poly on the market. Use it under the slab to stop moisture migration into the building. TUFF 4 will also retard the entry of soil gases, radon gas, and biological agents like mold which can seep into the building through cracks and bypasses in the basement slab.

• Tuff 4 has been independently shown to be 96.7% effective in retarding the entry of radon gas.
• TIP: Install TUFF 4 from the top of the foundation wall, over the footing, and under the drain tile. Seal seams with Venture Sealing Tape. Seal Those Seams!

Venture Sealing Tape is the one to use for sealing all the seams on your vapor barrier. Reduce leakage and achieve energy savings.

Independent tests by the National Association of Homebuilders show a 30% increase in performance when house wrap seams are sealed.