With stricter energy codes causing contractors to review their construction options, the opportunity to revise insulation choices arises. In some cases, contractors may be considering the use of spray-foam applications to replace fiberglass batt or loose insulation. Here are some factors to keep in mind:
1. Thermal performance. Fiberglass, in both blanket and loose fill forms, is a manufactured product. Created in plants under factory-controlled conditions, its manufacture follows established protocols. Continual testing verifies thermal performance and provides a high level of quality assurance. Spray-foam insulation is the product of two components that are mixed on site, which can affect its uniformity during its “manufacturing” process. Humidity and temperature, along with equipment efficiency and age, installer experience and other factors, can impact its consistency and in-place performance.
2. Air infiltration. Neither type of insulation inherently provides better protection against air leakage. A comprehensive field study by the NAHB Research Center of four insulation types (fiberglass batts, blown-in fiberglass, spray foam and wet-spray cellulose) found little differences in how they affected air leakage. Of more importance were the design, practice and experience of the individual installer. The more complicated the system is to install; the more variable will be the result.
3. Moisture control. Most spray foams have a minimal vapor retarder and will absorb water both in liquid and vapor form during the home’s life. This attribute means an added vapor barrier may be required to meet code or the homeowner’s needs, introducing new materials, labor and time. Time tested, durable design guidelines in all IECC climates are not available for builders.
4. Health and safety. Fiberglass insulation requires routine protective safety gear (goggles, dust mask and clothing coverage) during installation. Spray-foam insulation installation requires more stringent gear, including a fully enclosed suit with supplied fresh air for breathing. The risks of exposure with spray-foam products can be severe so no other workers may be in the area during application. It is also highly flammable at the time of application.
5. Sustainable design. Fiberglass insulation often contains recycled content, lowering its impact on a home’s footprint. Owens Corning EcoTouch insulation, for instance, contains a minimum of 58% total recycled content with 36% post-consumer recycled content and the balance pre-consumer recycled glass (content verified by Scientific Certifications Systems).
Code changes will create challenges that builders must address. Before they commit to a new design, however, they should look at all of the factors, including the intangible costs that may be overlooked but still impact the bottom line—and the homeowner’s satisfaction.
Editor's Note: This content is sponsored.