Step-by-Step

Uses: hot and cold supply lines; rarely for DWV (drain-waste-vent) lines. Flexible copper is also used for short final runs to fixtures.

Features and joining techniques: Rigid copper pipe is sold in 10' and 20' lengths. The most widely used pipe for supply lines. Lightweight and durable, though a bit expensive. Once the soldering technique is learned, you can cut it on the spot and put it together quickly. Type M is the thinnest, and is a good choice for home projects. Types L and K are used mainly in commercial projects. Flexible copper pipe is sold in 60' and 100' coils, or by the foot. It can be soldered but is usually connected with compression fittings.

Uses: supply and occasionally DWV

Features and joining techniques: Because it is cumbersome to work with and tends to build up lime deposits that constrict water flow, galvanized steel pipe is not used widely anymore. It takes expensive equipment to cut and thread it, so you must buy pre-cut pieces from your supplier. If you have a good selection of shorter pieces on hand, you can cut down on trips to the supplier. Black steel pipe is used only for gas lines.

Uses: Various types of plastic pipe are available. Some are suitable for drain lines only.

Features and joining techniques: For each type, you must use the appropriate cement or fittings. Ask your supplier to help select the best type for your needs. Also check that local codes allow the type of pipe you plan to use.

Uses: DWV

Features and joining techniques: Cast-iron is extremely heavy and difficult to work with, so don't try to install any new pipes of this material. Hub-and-spigot is joined with oakum and molten lead. No-hub pipe is joined with gaskets and clamps.