GALVALUME VS. GALVANIZED:
WHICH SUBSTRATE COATING SHOULD BE USED?
The substrate coating is used to inhibit rust. It covers the steel but is under the paint. Galvalume® uses a mixture of aluminum and zinc to protect against rust. Galvanized uses zinc only.
Galvalume® may begin to show rust around the edges of the panel before galvanized, but the rust should stop when it comes in contact with the aluminum in the substrate. Galvanized may take a few years longer to show edge rust; however, once the rust begins, it could continue to corrode the entire panel.
GALVALUME® OUTPERFORMS GALVANIZED LONG TERM
Galvalume® has been successfully used in building applications for more than 25 years; it has been evaluated in outdoor R & D tests for well over 30 years. Based on these tests, in which corrosion weight losses were measured and compared with galvanized, Galvalume® is projected to outlast galvanized (with an equivalent coating thickness) in various atmospheres by up to nine times.
Up to 10 years: Galvanized initially may be more effective, but does not sustain
10 to 15 years: Galvalume® begins to outperform galvanized
Over 15 years: Superior performance of Galvalume® is increasingly evident