Choose the right piping or tubing designed to house and protect wires that distribute power to your home

Conduit  Buying Guide

Conduit plays a vital role in protecting your home. It comes in rigid and flexible forms made from a variety of materials for use in different applications. It is most often used for protecting outdoor or exposed wires or cables.

This guide highlights the different types and materials used to make conduit and the accessories that are often used with conduit.

Metallic Conduit

There are two main types of metallic conduit: rigid and flexible. Rigid conduit offers solid protection, while flexible 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.
  • Prewired 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.
  • Running a green grounding wire is recommended, though code may allow the metal conduit itself to serve as grounding conductor.

Nonmetallic Conduit

Nonmetallic conduit also comes in rigid and flexible types, with benefits and specific uses for both.

  • Nonmetallic conduit is typically made from PVC and is a good choice for outdoor residential applications.
  • Blue electrical nonmetal tubing (ENT) is for indoor use only. PVC fittings can be used with ENT inside walls, floors, some ceilings or encased in concrete.
  • Outdoor flexible nonmetallic tubing is strong and watertight, non-corrosive and weighs less.
  • Metal or plastic boxes can be used with nonmetallic conduit.
  • Always run a ground wire when using PVC conduit.

Conduit Types Benefits and Considerations Uses


  • Steel tubing
  • Lightweight and easy to install
  • Can be bent or cut with the appropriate tools
  • Thin walls are more easily damaged or punctured than IMC or GRC
  • More affordable than IMC or GRC
  • Used most often in dry interior spaces
  • In damp locations use with corrosion-resistant hardware and rain-tight fittings


  • Thick, galvanized walls make it a good choice for exposed outdoor use
  • Can also be used indoors
  • Weighs less than GRC, so it’s easier to work with
  • Approved for all interior applications
  • Can be used outside


  • Highest level of protection
  • Available in galvanized aluminum, steel and stainless steel
  • Higher cost
  • Good for straight runways
  • Threaded ends require threaded fittings
  • Approved for all interior applications
  • Can be used outside


  • Spiral construction for high degree of flexibility
  • Easy to install
  • Commonly referred to as Greenfield
  • Useful in places where rigid conduit is difficult to install
  • Good choice for vibrating equipment, such as heating and air conditioning units


  • Available in metallic and nonmetallic
  • Runs across the surface of walls, allowing you to run cables and wires without cutting into the walls
  • Good for installing new switches, home theater systems, telephones and more
  • Can be painted to blend with existing décor
  • Use indoors for electrical or telephone wires, or audio, video data cables


  • Pre-wired conduit
  • Metallic sheath
  • Spiral construction for high degree of flexibility
  • Metallic armored cable is commonly known as BX or MC
  • For indoor use


  • Available in both metallic and nonmetallic configurations
  • Metallic configurations generally have a plastic coating to prevent water from penetrating
  • Protects wires from moisture
  • For use in wet or corrosive locations indoors and outdoors


  • Won’t corrode or rust
  • Requires a separate grounded wire
  • Most economical solution
  • Most common choice for electricians
  • Can be used indoors in walls or ceilings and outdoors
  • Good for in-ground and above-ground use


  • Lightweight and durable
  • Highly resistant to corrosive elements
  • Often used for data and communications cables
  • Good for in-ground use
  • Not used indoors