Earthwool Loft RollProduct Information Earthwool Loft Roll is a high quality insulation product made from sustainable, eco friendly materials designed to provide excellent thermal performance and sound insulation in loft spaces. Made from recycled glass and natural materials, Earthwool is a soft, flexible roll that is easy to handle and install in between joists, rafters, or under floors. It effectively reduces heat loss in winter and helps keep homes cooler in summer,