Spray foam insulation is a great choice because it forms a tight seal to moisture and outside air. Of course, some clients are concerned about indoor air quality when they hear the words "tight seal." It's certainly true that a lack of ventilation can lead to stuffy, polluted indoor air. However, this does not mean that one should avoid using spray foam insulation when building energy-efficient homes. It is still one of the most sustainable choices -- you just have to be sure to provide adequate ventilation to prevent problems with indoor air quality.
In most cases, ventilation for tightly sealed buildings is provided though the heating and air conditioning system. This way, some control can be had over the air that enters and leaves the building. Filters can be used to keep pollen and other allergens out. This is not a possibility when air is allowed to leak in through a drafty, unsealed building. Many ventilation systems use an air exchanger to pre-condition the air so that it's the proper temperature when it enters or leaves the building. This increases energy efficiency, allowing you to save on energy costs when you seal the building with spray foam insulation and install a high quality ventilation system.
Another air quality-related concern among clients who consider spray foam has to do with moisture and mold. Spray polyurethane foam does not trap moisture, however. In fact, most mold and moisture problems are caused by the leakage of moist air, and since spray foam prevents air leakage, it also prevents moisture buildup in walls. This leads to higher air quality as molds are less likely to form in dryer walls.
Contact NCFI Polyurethane to learn more about our products and services that help you when building energy-efficient homes.