Cold-rolled steel plates need to be painted every 2 to 3 years (at a cost of approximately 10 yuan per square meter), and the total cost over 20 years is about 80 to 100 yuan per square meter.
Hot-dip galvanized steel sheets (zinc coating 275g/m²) require no maintenance for 20 years, with a total cost of approximately 60-70 yuan per square meter, which is 20%-30% lower than that of cold-rolled steel sheets.
In indoor dry environments, cold-rolled steel plates are more economical because of their low initial cost and no need for anti-corrosion maintenance.
