What schedule pipe is galvanized water pipe required to be?

Galvanized water pipe is required to be schedule 40. This is primarily due to its capacity to meet the necessary pressure requirements typical in residential and commercial plumbing systems. Schedule 40 pipe has a sufficient wall thickness that provides durability and strength, making it suitable for carrying water under standard pressure conditions.

The wall thickness of schedule 40 ensures it can handle the stresses of water flow and any potential impacts from installation and service without compromising its structural integrity. Using a different schedule, such as 20 or 80, would not be appropriate; schedule 20 is too thin for most plumbing uses, while schedule 80, while thicker and suitable for higher pressure applications, is typically not needed for standard water piping needs. This makes schedule 40 the recognized standard for galvanized water piping.