Insulthane® 500 HY is a high performance spray foam insulation system that goes beyond traditional insulation in versatility and air sealing. During application, the product expands up to 100 times its initial volume, leaving no crack or crevice unfilled. While fiberglass batts and boardstock leave gaps that allow air to leak, Insulthane® 500 HY’s open-cell formula insulates and air seals in one step to form an extremely tight barrier against heat loss in the winter, and protects cooled air from escaping in the summer.