Is G60 Galvanized Type B Deck Enough for Florida Projects?
For most enclosed, conditioned Florida buildings, G60 galvanized Type B deck gives sound corrosion protection and is a common specification. G60 is the lighter of the two zinc coatings we offer. Use G90 near the coast, in unconditioned or humid spaces, and under wet-placed fills. We supply both in 22 through 16 gauge.
What G60 means
G60 is an ASTM A653 coating designation. The number is the zinc coating weight in hundredths of an ounce per square foot, counting both sides. The zinc shields the steel and corrodes sacrificially at scratches and cut edges, so small damage does not start rust right away.
Where G60 fits and where it does not
- Good fit: offices, schools, retail and other conditioned buildings inland, with a sealed roof membrane.
- Check with the engineer: buildings within the reach of salt air, pool and natatorium areas, kitchens and wash bays.
- Usually G90: open canopies, unconditioned warehouses, parking structures and roofs with lightweight insulating concrete.
Get it specified and quoted
The coating class should come from the project specification, not from the supplier. If the specification is silent, raise it with the architect before you buy. Send us the plans and specification section and we will price 1.5" Type B in the coating your documents call for.
Related Questions
Does G60 change the structural capacity of Type B deck?
No. Section properties and load tables are based on the base steel design thickness. For 1.5" Type B that is 0.0295" at 22 gauge, up to 0.0598" at 16 gauge, with Fy of 50 ksi. The coating adds corrosion protection, not strength, so G60 and G90 deck of the same gauge carry the same loads.
Can G60 deck be painted later?
Yes. Galvanized deck is often field painted where the underside is exposed to view. Galvanized surfaces need proper cleaning and a compatible primer, so follow the paint manufacturer's surface preparation instructions. The architect usually specifies the system, and the painter should know whether the deck is G60 or G90 before choosing a primer.