Roofing Manufacturers:

GAF Materials Corp
Johns Manville
Firestone
Carlisle
Tamko Building Products
Soprema
Owens Corning
Sarnafil
mcelroymetals
Fabral
Petersen Aluminum
IMETCO
AEP Span
ER Systems

Organizations:

Copper.org
ASTM International
Underwriters Laboratories
RCI
FM Global
National Roofing Contractors Association