Galvanized pipe is steel tubing coated with a protective zinc layer, historically used for water supply and drainage in residential and commercial buildings. The zinc coating provides corrosion resistance, extending pipe lifespan to 40 to 50 years in most conditions. Galvanized pipe was the standard for water distribution before copper and PEX became prevalent.
Technical Specifications
Galvanized pipe operates safely between 32°F and 212°F, suitable for both hot and cold water. It handles pressures up to 150 PSI. The zinc coating is typically 45 to 85 microns thick, with thicker coatings providing greater protection. Standard sizes range from 1/2 inch to 2 inches diameter.
HVAC Water Applications
Galvanized pipe is occasionally used in older heating systems for hot water distribution and boiler connections. It can handle moderate temperatures in low-flow heating circuits. However, its tendency to accumulate mineral deposits inside reduces flow efficiency over decades.
Current Status and Limitations
Most jurisdictions have phased out galvanized pipe for potable water due to corrosion risks and mineral buildup. It remains acceptable for drainage applications and non-potable water. Galvanized fittings use threaded connections, requiring wrenches for assembly. Modern HVAC installations prefer copper or PEX for superior performance and longevity.