The two main types of metallic conduit are rigid and flexible.
Rigid conduit offers solid protection, while flexible metal conduit allows for bends and twists without the use of extra hardware.
- Rigid metallic conduit is most often used in commercial applications but can be a smart choice for straight runs of wire or cable through an attic, garage, basement or crawlspace.
- It protects against nicks, cuts and punctures to wiring from accidents or chewing animals.
- Examples are electrical metallic tubing (EMT), which is lightweight and easy to install; intermediate metallic conduit (IMC), which has a thicker, galvanized wall, making it suitable for outdoor applications; and galvanized rigid conduit (GRC), which is thickest and offers the most protection.
- Flexible metallic conduit bends and twists easily, allowing turns at corners without the use of elbow joints.
- Pre-wired conduit, or armored cable, offers an all-in-one solution with the wires already running through it.
- Metal electrical boxes must be used with metal conduit.