Metallic vs Non-Metallic Flexible Conduits

Flexible conduit is pipe or tubing used to protect and route electrical wiring in a structure. They can be various materials, including metal or plastic.

There are two main types of conduit: metallic and non-metallic. Each has advantages and disadvantages to consider while choosing conduit for a particular application.

Metal conduit is usually made of aluminum or steel. It is strong and durable, making it ideal for applications requiring mechanical protection for wiring. However, metal conduit is more expensive than a non-metallic conduit and is subject to corrosion.

Non-metallic conduit is made of plastic, such as PVC or HDPE. Non-metallic conduit is less expensive than a metallic conduit and is not subject to corrosion. However, non-metallic conduit is not as strong or durable as metallic conduit and may not provide the same level of mechanical protection.

When choosing between metallic and non-metallic conduits, it is essential to consider the application’s specific needs. Cost, durability, flexibility, weight and temperature or corrosion resistance are important factors to consider. The right type of conduit will depend on the application’s particular requirements.

Now, let’s dive into the similarities between the two conduits.

Metal and Non-Metallic Conduit in Use

Similarities among a metallic conduit and a non-metallic conduit

Metallic conduit and non-metallic conduit have these similarities:

  • Both are composed of materials that are strong and durable, making them ideal for electrical wiring applications.
  • Both types of conduit are designed to protect and route electrical wiring.
  • Both metallic and non-metallic conduit are available in various common Trade sizes to accommodate different applications.
  • Both are suitable for use in domestic, commercial, and industrial buildings and structures.
  • Both protect against fire, mechanical damage and corrosion.
  • Both may be rated for electrical safety applications according to the National Electrical Code (NEC).
  • Both have adequate electrical field shielding and flexural stiffness (resistance to deformity).

Differences between metal conduits and non-metal conduits

Here are key differences between metal and non-metallic conduit to consider:

Non-metallic conduit

Here are some of the advantages of using non-metallic conduit:

  • It can be used for fixture whips, data centers, electric signs and outdoor lighting, HVAC, pool and spas, and locations with exposure to sunlight and weather conditions.
  • It is less expensive than most metal conduit.
  • It is easy to cut at the site of installation.
  • It is lighter weight than most metal conduit.
  • It is more flexible than most metal conduit, making it easier to route through tight spaces.
  • It may be installed in wet locations and buried in the ground or in concrete.
  • It may be installed indoors, outdoors, under ground and above ground.
  • PVC conduit may be recycled multiple times.

Here are some disadvantages in use of non-metallic conduit:

  • It is not as resistant to crushing force, even though it may rebound from impact.
  • Most non-metallic conduit is not rated for high or low temperature extremes
  • It is not permitted in hazardous areas where the ambient temperature exceeds 50°C (122°F) or in applications where the conductor insulation temperature exceeds the rated temperature, such as extreme cold.
  • It cannot be installed in plenum environments due its flammability and possibility for generating toxic smoke or fumes in a fire.
  • It cannot be used without physical support along its installed length.

Metallic conduit

The following are the advantages of using metal conduits:

  • Metal conduit is durable and can last many years with proper maintenance.
  • Galvanized steel, aluminum, stainless steel, bronze and brass conduit is recyclable, making them a more sustainable option than other materials.
  • It can withstand extreme temperatures and conditions, making it an ideal choice for protecting electrical wiring in harsh operating environments.
  • It is resistant to impact and temperature changes, making it an ideal choice for protecting wiring in high-traffic areas or areas subject to extreme temperatures.
  • It is made of non-combustible material, making it an excellent choice for protecting wiring for fire safety applications.
  • It can be rated for electrical safety applications.
  • A metallic conduit is easy to machine or fabricate, making it ideal for applications that require custom sizes or shapes.
  • Extruded polymer jackets meet or exceed industrial chemical resistance requirements.
  • Polymer jackets provide liquid tight protection allowing installation in wet conditions, or burial underground or in concrete.
  • Polymer jackets provide low smoke or Halogen free protection of wiring.
  • A integral bonding wire may be included in metal conduit, supporting NEC approved use in electrical connections.

However, using a metallic conduit also has some disadvantages, including:

  • It costs more upfront to purchase the materials and install them.
  • It does not offer full protection for circuits above and below ground against hazards, without a liquid tight jacket.
  • It is heavier than a non-metallic conduit.

Flexible metallic & non-metallic conduits from Anamet Electrical

Key differences in these conduit types is material, durability and cost.

Metal conduit is more expensive than non-metallic conduit but it offers better protection from fire, pests, and extreme temperatures. They are also more durable and have a longer lifespan.

Non-metallic conduit is made of plastic or other material, less durable than metal. However, is it less expensive, lighter weight, more flexible and more corrosion resistant.

Anamet Electrical, Inc. has over 100 years of experience manufacturing quality flexible conduit for electrical wiring. Our liquid-tight metal and non-metallic conduit types are available for protecting mission-critical wiring from harsh operating conditions on land, at sea and in the air.

Our flexible metallic conduit and non-metallic conduit are available in various sizes and lengths. They can be custom-ordered to meet your specific needs.

If you’re looking for a high-quality, reliable, and durable conduit solution, look no further than Anamet Electrical. Contact us today to learn more information about our products and services.


  1. John K. Boren

    Can flexible metal conduit (FMC) be used to facilitate a power drop in an industrial facility? Can it support its own weight, as it will be hanging from the rafters.

    • Jonathan Middleton

      We cannot recommend free hanging flexible conduit. We can’t know how much motion, strain or strain relief your application would cause or allow.
      Please see National Electrical Code Article 350.30 Securing and Supporting LFMC, with support required every 4-1/2 feet, no definition between vertical or horizontal.
      Check with your local code inspector for variance.

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