G90 galvanized steel has a longer service life than g60 g40 and g30 galvanized steel because g90 galvanized steel has a heavier coating weight of zinc applied to it at 0 90 oz ft 2 as opposed to g60 galvanized steel at 060 ox ft 2 and so on.
G60 vs g90 sheet metal.
Similarly a g90 coating is approximately 50 thicker than a g60 coating and thus would be expected to perform 50 better in terms of time to 10 rust.
G90 designates a coating of 0 90 oz square foot.
Temperature exposure moisture etc with a linear relationship between coating thickness and ability to resist corrosion.
G90 is not a galvanizing specification.
G30 g40 g60 and g90.
There are other thickness of coating g140 which designates 1 40 oz square foot g60 which designates 0 30 oz square foot.
2003 this entry appended to this thread by editor in lieu of spawning a duplicative thread.
How long will a galvanized g40 g60 g90 coating last.
4specs discussion forum a60 vs g60 galvanized steel.
90 signifies the quantity of the zinc coating on the steel sheet.
In other words a g60 coating has twice the thickness of a g30 coating and the life of the product in a given environment is approximately twice as long.
If it is for outdoor use or in a high moisture environment i would always specify g90 just because it seems to make a difference over time.
With steel sheet there are several fabrication processes that it takes to make it into not just a stud but a stud wall.
Nonetheless it is a coating of steel sheet before fabrication.
I believe that the g90 coating for steel sheet is a coil coating.
I hope this helps steve sarten.
The g60 is the most common galvanized metal and determines the amount of galvanize on the metal.
G30 g60 g90 galvanized coils and sheet g30 g60 g90.
Understanding zinc based coating weights.
This weight is the total weight of zinc on both sides of the sheet i e 0 45 oz square foot on each side.
The g90 would be more galvanized coating than say g60.
Limits on maximum acceptable coating weights for an application are usually given by other factors such as cost or formability.
How long the galvanization lasts depends primarily on the site conditions i e.
Hot dipped galvanized coatings.
Galvanized steel in everyday use.
Also for use in sheet metal.
Generally speaking if a g30 coated steel product lasts five years until it starts to red rust or corrode then a g60 will last 10 years and a g90 will last 15 years.