Economical
	Pound for pound, steel is the most economical metal roofing and siding material
	Today, steel is a high-tech, engineered material
	The life cycle costs of steel roofing and siding are very attractive
	Steel companies in the United States are competitive worldwide with regard to quality and cost

Strong and Durable
	Steel is strong and can be used in either structural or architectural roofing and siding
	Bare GALVALUME® Coated Sheet roofs and sidewalls are warranted against perforation for 20 years
	Steel resists damage from wind, hail and snow
	Available in minimum yield strengths up to 80ksi

Recycled Content
	Steel is the most highly recycled material on the face of the earth
	Nearly 64% of all steel scrap in North America is recycled annually
		60.7% of all steel packaging is recycled
		81% of all steel appliances are recycled
		97.6% of all steel automobiles are recycled
	When steel roofing and siding have completed their useful life, they can be easily recycled and not landfilled
	Steel roofing has a minimum recycled content of 25%

Steel is made by two general processes: integrated steelmaking and electric furnace steelmaking. Most steel for roofing is made by the integrated steelmaking process.
Integrated Steelmaking Process
	Molten iron is made in a blast furnace	View the Integrated Steelmaking process
	The iron is refined into steel
	The steel is continuously cast into slabs
	The slabs are rolled into hot-rolled coils
	The hot-rolled coils are cold reduced
	The cold-rolled coils are metallic coated (galvanized, GALVALUME®, Galfan, aluminum coated)

Hot Dipped Coating Process
	The cold-rolled strip is cleaned in a caustic bath, continuously annealed in a high-temperature furnace, and immersed in a bath of molten zinc, aluminum-zinc, etc.	View the Hot-Dip Coating process
	Coating thickness is controlled by high- pressure computer-controlled air knives
	The strip is cooled and flattened by tension leveling
	Surface quality is enhanced by temper rolling
	Acrylic coating is applied to GALVALUME® Coated Sheet (creating ACRYLUME® Coated Sheet) or galvanized (creating ACRYZINC® Coated Sheet)

Coating Chemistries
	Galvanized - 100% zinc
	GALVALUME® - 55% aluminum, 45% zinc
	Galfan - 95% zinc and 5% aluminum

Coating Weights
	Galvanized for roofing is produced in either G60 or G90 coating weights
		G stands for galvanized
		60 and 90 stand for 0.6 or 0.9 of an ounce coating per sq. ft. total both sides
	GALVALUME® is produced in either AZ50 or AZ55 coating weights
		AZ stands for aluminum/zinc
		50 and 55 stand for 0.5 or 0.55 of an ounce coating per sq. ft. total both sides

Common Coated Sheet Specifications
	General requirements for hot-dipped coated sheets - ASTM A924
	Hot-dipped galvanized sheets - ASTM A653
	GALVALUME® Sheets - ASTM A792
	Galfan - ASTM A875

Metallic Coatings There are two general types of metallic coatings used to resist corrosion:
	Sacrificial - coating reacts to protect steel in corrosive media
		GALVALUME®
		Galvanized
		Galfan
	Barrier - coating provides barrier against corrosive media and is not as reactive
		GALVALUME®
		Aluminum coated

GALVALUME®
	GALVALUME® is a unique combination of both a sacrificial and barrier coating
	The zinc provides protection on exposed edges and places where the coating may become scratched
	The aluminum provides an excellent barrier to corrosive media

Types of Paints

Generic  Coating  Type (1)  Humidity  Resistance  General  Corrosion  Resistance (2)  Color  Permanence  Abrasion  Resistance   Acrylic   Very Good   Good   Good   Good   Polyester   Very Good   Good   Good   Good   Siliconized   Polyester    Good   Good   Very Good   Good   PVC   Plastisol (3)   Excellent   Excellent   Good   Excellent   Fluoro-   polymers   PVDF   Excellent   Very Good   Excellent   Very Good

Generic  Coating  Type (1)  Gloss  Retention  Formability  Chalk   Acrylic   Good   Good   Good   Polyester   Good   Very Good   Good   Siliconized   Polyester    Very Good   Good   Very Good   PVC   Plastisol (3)   Good   Excellent   Good   Fluoro-   polymers   PVDF   Excellent   Excellent   Excellent

(1) This table lists common coatings. It does not list all of the available coating variations. Generally, most systems are one mil (0.001 in. or 25 microns) thick except where noted.
(2) Includes resistance to severe natural and industrial environments.
(3) Four mils (0.004 in. or 100 microns) or greater coating thickness.

Source: National Coil Coaters Association