Consider Moisture Issues When Choosing Insulation

By Scott McGillivray
We insulate our homes primarily to keep them warm in the winter and cool in the summer. As a result, most of us evaluate insulation based on its thermal properties, which is definitely important to consider. However, there is another aspect of wall and ceiling insulation that should be considered before making a final decision, and that’s moisture. If you choose the wrong insulation, moisture can seriously damage the long-term performance of the insulation, drastically reducing the benefits it offers to your home.
Although wall and ceiling cavities may be out of sight after a home is built, they are very important spaces in residential construction and remodeling projects. They play a critical role in managing the interior temperature, noise level, air-flow and mold levels. It is important that the insulation in the walls and ceilings works just as well years after installation as it does the day after the project is completed. This means that the insulation needs to stay consistent over time –– any sagging, compressing or rotting will compromise the safety and comfort of your home.
To combat these potential problems, look for insulation that does not absorb water, but repels it. Stone wool insulation, like that produced by Roxul, is a good choice. Water-resistance is important year-round, but especially in summer, when humidity levels rise, and in spring and fall, when rain and moisture levels can increase dramatically. It’s vital that your insulation won’t compress or sag within the wall or ceiling cavity, because when insulation materials compress and sag, they leave gaps, compromising the thermal performance of the wall. Cold, heat and sound can pass through much more easily, creating a living space that’s less comfortable and more expensive to heat and cool.
Another important consideration when choosing insulation is mold resistance. Materials that resist mold growth, like stone wool, are essential to the health of your home and family. Because mold feeds on organic matter, selecting an insulation that is composed of nonorganic matter is ideal to prevent rot.
Keeping moisture and mold at bay with a quality insulation will contribute to a safer indoor environment and provide energy savings and comfort benefits that can last for the lifetime of a home.