Energy Efficiency — Retrofitting Your Home with Vapor Barrier & Air Sealing

Moisture movement into exterior walls”. Any where air can move, so too can water in the form of moisture molecules. Traveling via air paths and moved by the force created by negative to positive air pressure, moisture often finds it’s way inside the tiniest of tiny crevices in a wall and condenses on colder objects. Repeated exposure to moisture on structural members of a wall can, over time cause deterioration and structural damage. Non-structural members and other materials inside a wall exposed to moisture repeatedly can create ideal conditions for mold to thrive. Mold, as many people know, is toxic to humans when aspirated.

I am often asked why air sealing is so necessary to conserving energy in a home and people are often under the impression that air sealing is a bad thing. That’s because before our concern about conserving energy, most homeowners and builders have come to rely on a drafty house to create fresh air. Well, I hate to break it to you but the air outside is not exactly fresh. Especially, if you live in a city which is located directly under flight paths to many larger centres in the United States, as I do. To add to this pollution is more pollution created by unnecessarily wasting fuel and money that is spent in drafty homes.

Some people believe that using vapor barrier and sealing all cracks big and small, will create build up moisture inside the home. I’ve heard so many times, “Houses need to breathe” and they do but in a controlled way that doesn’t waste heat and energy unnecessarily, through mechanically exhausted fans & range hoods to the outside of the home. The Attic however, is the place that needs to breathe and be kept cool. Air should flow through the attic to keep it fresh but it still should be done in a controlled manner through the use of soffit vents, ridge vents and other variations on vents.