Roof membrane made with Elvaloy® KEE provides durable protection for huge packaging plant in Florida.

• Life in a hot, humid tropical climate
• Installation methods suited for a large, complex building project
• Outstanding chemical resistance

To meet these needs, International Paper (IP) specified a single-ply membrane based on DuPont Elvaloy® ketone ethylene ester. Cooley Roofing Systems, Inc., Pawtucket, R.I., filled the bill with its "C-3" membrane.

IP's new Florida facility near Tampa is the largest packaging plant in the U.S. It turns out millions of printed, coated paperboard containers for orange juice, drinks and other products every week.

"Ultraviolet light, heat and humidity are all factors to consider in southern Florida," says John Smith, vice president of new business development at Cooley Roofing. "'C-3' with Elvaloy® is ideal for tropical environments. Because of their thermoplastic nature, roofing membranes based on Elvaloy® can be heat welded, making installation and future 'add-ons' easy. Elvaloy® is a high molecular weight, non-migrating polymer which helps our 'C-3' product maintain its flexibility, appearance and color after exposure.

Installation Benefits

The installation of 160,000 square feet of roofing was a complex task. Use of a thermoplastic membrane with Elvaloy® provided additional value to IP because of its ease and efficiency of installation. Unlike some other types of membranes, the thermoplastic membrane with Elvaloy® proved ideal for an efficient two-stage installation regime employed by the roofing contractor, Neth & Son, Lake Buena Vista, Fla.

Using a hot-air welding process, Neth's crews first installed a monolithic roof, then came back on several occasions to do cut-outs and detail work as mechanical systems were installed.

For monolithic roof installation, the contractor worked with "C-3" membrane supplied on rolls which were 750 square feet each. Overlapping seams were used to form watertight bonds as strong as the membrane itself.

John Manzella, general manager at Neth & Son, said, "The single-ply membrane made it easier to get the job done in a timely fashion. It was also easy to repair minor tears occurring during construction."

Inspection shows that welded seams provide durable watertight seals around mechanical elements even though they were added many months after initial installation of the roof.

The toughness of the membrane provides benefits both during installation and in service. The compound based on Elvaloy® forms a bond to the reinforcing fabrics used in membrane construction. This applied engineering is a key factor in the integrity and durability of the membrane structure, according to Smith, providing extra puncture and tear resistance. "If a tool is dropped on the roof, the membrane does not tear easily; but it is easily repaired if damage does occur," he said.

Chemical Resistance

In addition to providing exceptional weather resistance and installation advantages, the membrane made with Elvaloy® meets International Paper's needs for chemical resistance. The plant complies with emission requirements. The roof must nonetheless provide long-term resistance to solvents, inks, air conditioning coolants, oil and grease and air pollutants.