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Durability of G60 galvanized Steel

 

Can you please let me know if there is any statistical information as to the durability & life span or structural astuteness of G60 galvanized steel.

Thanks,

Tonya Booker
trusses & panels. - Markham, Illinois

Hi, Tonya. G60 means .60 ounces of zinc per square foot, but includes both sides of the sheet; so the weight is .30 ounces per square foot per side. If we estimate the density of the coating as the density of zinc, 7.14 g/cc or 4.127 oz/in3, this would be 0.0727 in3/ft2, or a thickness of approximately 0.005 inches thick.

In letter 7666, it is suggested that G90 (which would be 1.5X as thick) should be the minimum used for outdoors exposure. Patient application of the search engine will reveal many threads where industry experts consider G60 to be thin and (by implication) questionable. I don't think the galvanizing thickness has any effect on the structural astuteness.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 1, 2009