Cold Applied Roofs

Travis County Correctional Complex, Del Valle, Texas
Travis County Correctional Complex, Del Valle, Texas

 

For many years, cold adhesives and hot asphalt were considered effective ways to secure insulation panels and other elements to steel roof decks. These techniques were fast, eliminated roof penetrations, and allowed damage-free re-roofing. However, in the 1970s insured’s of Allendale Insurance, Arkwright and Protection Mutual Insurance and others began to experience numerous wind-related losses due to the failure of adhesive-adhered roof systems.

While many adhesive-roofing systems performed well in laboratory testing, these same systems failed in the field under real-world conditions such as hurricanes, tornadoes, hailstorms, and other weather extremes. As losses mounted, Factory Mutual Research stopped granting Approvals for the use of adhesives in applying the first layer on steel roof decks. The reasons for the failure of adhesive- and asphalt-adhered roofs are many and include poor installation practices, product failures, improper maintenance, and extreme weather.

But many building owners, especially in the food processing and computer circuit manufacturing industries, request adhesive- adhered roofs in order to reduce or eliminate roof penetrations, which can cause contamination. Other reasons for requesting adhesive-adhered roof systems include reducing construction and re-roofing noise, and reducing roof damage during re-roofing.

Thanks to improvements in adhesive technology in recent years, Factory Mutual Research has drafted a new Approval standard (4460), Class 1 Cold Adhesive Applied Insulated Steel Deck Roof Construction. The expected effective date for the new Approval standard is sometime late in the year 2000.

The new Factory Mutual Research Approval standard has been developed based on recent (positive) loss experience, research and testing. In addition, the advice of manufacturers, end users, trade associations, and loss control specialists was also considered in the development of the new standard.

A Class 1 cold-adhesive-adhered insulated roof system must meet Factory Mutual Research criteria for resistance to fire, wind uplift and live loads. In addition, adhesive roof systems will be evaluated in the field and must demonstrate a minimum of five years of successful performance history. Factory Mutual Research will also audit manufacturers to evaluate manufacturing facilities and quality control procedures.