Abstract: Building structures, such as pre-engineered metal buildings, concrete buildings, and combination concrete and metal buildings in most areas require insulation due to the relatively high thermal conductance of the metal and concrete components in the buildings walls and roof. Because of energy conservation measures brought on by fuel shortages and rapidly rising fuel costs, insulation systems used in the past are generally not adequate to meet more stringent standards either recently established or planned for the near future. The present invention provides an improved insulation system for use in either new construction or in reinsulating existing building structures.