Galvanized Steel Pipe

Galvanized Steel Pipe
Common in many older homes. It was used for both water supply and waste water lines. "Black-pipe" (non-galvanized steel pipe) is still used for gas piping.

Rust tends to build up on the inside of the pipes. While this rust is reported to have few if any health consequences, it does reduce water flow and may also cause leaks in the pipes.

In waste water lines, galvanized pipe has the disadvantage of having rough surfaces and thus clogging more easily.

Galvanized pipe installation work usually requires threading tools or the purchase of specific lengths of pre-threaded pipe. Galvanized Steel Pipe

Some galvanized pipe with some early signs of leaks.

Article: 
Choosing Pipe