Metallic vs. Non-Metallic Conduit

Metallic vs. Non-Metallic Conduit

Wire and cable protection is vital for safe and effective applications. While various conduits can defend against wear and corrosion, some are better suited to specific projects and working environments.

You can secure your wires and cable against water, heat, corrosion and intrusion damage with suitable conduit materials. Weighing the differences between metallic and non-metallic conduits can help you select the right materials and protection levels for your applications.

How Are Metallic and Non-Metallic Conduits Similar?

Metallic and non-metallic conduits can both protect electrical wiring in various applications like heating, outdoor lighting and underground cabling. A metal conduit is made with stainless steel that is galvanized and coated as well as aluminum — perfect for withstanding harsh conditions like extreme heat and cold. Metal conduits are excellent for industrial applications like protecting wiring on railway lines and cables in walls and floors.

How Are Metallic and Non-Metallic Conduits Similar?

A non-metallic conduit is made from materials like polyvinyl chloride (PVC), polyamide, polypropylene and polyurethane — excellent for installing in tight spaces like HVAC systems. Businesses can use pliable conduits in numerous outdoor and indoor applications, like protecting indoor residential wiring and cables in swimming pools.

Similarities of Metal vs. Plastic Conduits

Here are some similarities between metal and plastic conduits.


Plastic and metal conduits are both used to protect electrical wiring. Plastic options are versatile, perfect for commercial and residential applications like underground cable insulation in irrigation systems and building surfaces. Metal conduits are sturdy and reliable for protecting aerospace and automotive equipment wiring and resending electrical ceiling wiring.


Both metal and plastic conduits can withstand moisture, heat and corrosion like rust. Metals like steel and aluminum are robust and resist tears, cuts and other damage. PVC and other plastic materials can be rigid and are wear-resistant and chemical-resistant. They can also repel fires and electrical hazards.

Size Options

You may need conduits for a wide range of applications, from bridge construction to HVAC systems. Whatever your requirements, both metal and plastic conduits come in various sizes that fit numerous functions.


Plastic and metallic conduits can prevent electrical fires and provide insulation from mechanical damage. Plastic options can be fire-resistant and can contain the spread of fire. While metal is an electrical conductor, metal conduits are fireproof and can transport electric power safely to the source.

What Is the Difference Between Metallic and Non-Metallic Conduits?

While metallic and non-metallic conduits can serve the same purposes, they differ significantly. Understanding and comparing their differences can help you decide which option to choose.


Non-metallic conduits can be less expensive than metallic. Metals are thicker than plastic and can cost more to manufacture. Metal conduit manufacturing can also require more intricate tools and specialized skills, and the manufacturing timeline can be longer. Plastic is a lighter material and takes less labor to manufacture. Plastic can also be more readily available for conduit manufacturing.


Businesses can use non-metallic conduits for applications like residential wiring in concrete surfaces and walls to protect against electrical faults and fires. In addition, PVC conduits are great for securing electrical ceiling wires.

Rigid metal conduits are ideal for exposed cables along building walls, attics and outdoor areas. Applications for flexible metal conduits include more complex, high-pressure environments like wiring in aerospace equipment. Steel conduits can also be used as grounding or earth conductors to carry electrical current safely through power supplies.


Plastic can weigh less than metal conduits, making it easier to install these options in various positions and at different angles. Rigid metallic conduits are often heavier, but are ideal for withstanding heavy loads and underground environments.


When it comes to durability, metal is the more robust material overall. Metal conduit can withstand extreme high and low temperatures and last for many years. For example, businesses can use metal conduits for grounding wiring in snow and extreme heat as well as high vibration and force on railway lines.

Corrosion Resistance

Non-metallic conduits can often withstand wear and corrosion like warping, rotting and rust better than metal counterparts. While businesses can use metallic and non-metallic options in damp, humid locations, metal conduits may require a plastic coating to prevent water and chemical damage.


If sustainability is a priority, metallic conduits are typically a more eco-friendly option. Aluminum is one of the most reusable materials, though many plastics like PVC are also recyclable.

Safety Rating

While metallic and non-metallic options can be safe for numerous uses, rigid metallic conduits often have a higher electrical safety rating since they resist high electrical voltages and can protect against electrical hazards.

Which Type of Conduit Should You Use?

Consider factors like size, cost and safety to select the right conduit solution for your needs.

Safety Requirements

It’s important to follow local and national safety regulations when selecting an electrical conduit. Various safety codes offer specific directions on conduit installations, inspections and circuit approvals. Businesses must also choose conduit materials that are appropriate for their specific application.

To ensure safety, it’s essential to consider factors like moisture, wear, pests, vibrations, chemical resistance and heat resistance depending on industry application, location and conditions.


A conduit should be the right size for the specific job at hand. Determining the proper conduit diameter is crucial to ensure a secure fit and prevent moisture damage. It’s also important to think about application in order to choose the right size. For example, underground electrical protection can require longer conduits, while a heating system may need shorter or smaller tubes.

Project Goals

Various conduits offer benefits like liquid resistance, flexibility and easy installation, so your choice should align with the specific project’s goal.

For example, a liquid flexible metal conduit (LFMC) can offer hardness and water resistance and is versatile — ideal for protecting wiring in water treatment facilities. In contrast, liquid-tight flexible non-metallic conduit (LFNC) can be suitable for interior and exterior use in dry or wet conditions like wire protection in HVAC systems.

Conduit Fittings

Selecting a suitable conduit fitting material is vital. Whether the fitting is plastic or metal, it must offer the same moisture resistance and corrosion resistance as the conduit. Consider fittings like liquid-tight plastic for liquid-tight conduits or metal fittings for rigid metallic conduits.

Customization and Availability

Equipment and projects can vary, requiring specialized conduits, fitting designs and sizes. Consider suppliers who can tailor conduits and fittings to meet various requirements. In addition, some parts can take longer to manufacture than others, so determine the availability of options and if a supplier can meet project demands on time.

Find the Conduit Material for Your Application at AerosUSA

Find the Conduit Material for Your Application at AerosUSA

AerosUSA provides premium quality wire and cable protection. With over 10 years of industry experience, we know the importance of getting the right conduits for your applications. We offer a range of conduit and fitting materials to meet your project requirements, whether you need non-metallic or metallic options.

Browse our selection or contact us for assistance with your next project.

Reviewed for accuracy by: George Sims.
George Sims is an engineering and service-oriented leader in Cable Protection and Cable Management Products. Focus is on 100% commitment to customer satisfaction. AerosUSA is a small, agile, independent company whose focus is on our customers.