PVC vs Metal Conduits

What are the Different Types of Conduits?

Rigid Metal Conduits

Rigid metal conduits (RMC) are generally steel and create a threaded raceway with thick walls and a circular cross-section. Thicker steel walls increase the integrity of the conduit and can prevent it from being dented and becoming damaged. Steel has a high tensile strength rating, so it is less likely to bend and break under tension.

Aluminium is sometimes used for this type of conduit and is lighter and more resistant to corrosive elements, at the cost of reduced raw strength compared to steel.

Electrical Metallic Tubing

Electrical metallic tubing (EMT) is a threadless metal tube system with thinner walls compared to RMC. This means that it does not offer the same kind of protection as RMC, but can be connected together more easily and is both a lighter and more cost-effective option.

This style can be concealed behind a wall, run across a surface exposed or buried. If burying this conduit is your plan, choosing piping that is either galvanised or stainless steel is a better way of repelling those corrosive elements. Aluminium is an option for this tubing too, but it will eventually corrode if installed in the ground.

Flexible Metal Conduit

Flexible metal conduits (FMC) are created with a corrugated spiral structure that can be bent around more complex areas for installation. A great choice for moving wires through walls, structures or more narrow spots. This tubing tends to be used in dry indoor areas.

Electrical Non-Metallic Tubing

Similar to FMC, electrical non-metallic tubing (ENT) is a flexible plastic tubing made with a corrugated structure. The plastic used in its manufacture is both moisture and flame-resistant. This is a cheaper option that is easy to manipulate and bend, but can only be used in indoor areas, such as walls, ceilings and floors that won’t be exposed to too many hazardous elements.

Intermediate Metal Conduit

From a less hardwearing option in ENT to one of the sturdiest options, intermediate metal conduits (IMC) are essentially RMCs that have been designed for outdoor exposure and highly secure connections. These tubes are coated internally to resist corrosion and externally with a hot galvanised coating for better resistance. This type of conduit can be used in commercial and residential areas.

Rigid PVC Conduit

Rigid PVC conduits are a popular choice thanks to their strength and versatility. It can be installed anywhere from home use to industrial areas. It is robust, waterproof, UV-resistant, non-magnetic and has a long lifetime.

PVC Coated Conduit

PVC-coated conduit offers the ideal combination of metal strength and PVC protection. After the steel conduit is galvanised and threaded, it is coated with layers of polyurethane and PVC. This process provides the structural advantages of metal, like durability and effective grounding, alongside the corrosion and rust resistance of PVC.

The result is a long-lasting, reliable solution for electrical conduit systems, especially in environments where corrosion is a concern.

PVC Conduits Overview

Polyvinyl chloride, more commonly known as PVC, is a highly resistant synthetic resin that has been a popular material for conduits to protect electrical lines and other utilities since the late 1950s, replacing rubber alternatives. This section will highlight the advantages and uses of PVC.

Advantages of PVC Conduits

• PVC conduits are a robust barrier with high impact resistance and general strength
• It is a great insulator for electrical wiring and can prevent short circuits
• Simple fittings and connections with its lightweight, malleable design means it is easy to install
• PVC is a cheaper material to buy
• Has a long life span with minimal maintenance
• A trusted and sustainable material

PVC Conduit Uses

PVC is a strong all-around choice for your cable management solutions. It is ideal for underground use as it is resistant to rust, corrosion and other elements. It is a lightweight and flexible material that is easier to install and can be a great option when weight needs to be considered. Furthermore, it is also a more cost-effective solution than metal conduits.

PVC can be used almost anywhere that won’t be susceptible to high temperatures. 

Metal Conduit Overview

Metal conduits most commonly use aluminium, galvanised and stainless steel. This type can be more versatile in application compared to PVC and is a popular and durable choice for particularly harsh environments. This section will explore the advantages of each common metal type and its uses, to find out which is better with PVC vs metal conduit.

Advantages of Metal Conduits

Aluminium

• Aluminium is around 1/3 of the weight of galvanised steel
• Can often be a more cost-effective choice
• Recyclable
• Provides electromagnetic interference (EMI) shielding
• Naturally resistant to rust and corrosion

Galvanised Steel

• The zinc coating protects the steel from rust, moisture and other corrosive elements
• Galvanised steel can effectively block any EMI
• Conduits made from this provide an electrical ground, increasing their safety ratings
• Versatile in its applications
• Resistant to fire, the zinc coating and the metal itself have a significantly higher melting point than aluminium

Stainless Steel

• Exceptionally high durability and tensile strength
• Resistant to both extreme cold and hot temperatures
• Also recyclable
• Can be used in flexible conduits
• Reduces EMI
• A reliable choice to resist rust and corrosion

Less Common Metals (Bronze and Brass)

• Bronze has a high corrosion resistance, including saltwater
• Bronze is one of the most durable metals available
• Brass is a conductor and is great for reducing signal loss in electrical systems
• Brass is a more affordable alternative to Bronze

Metal Conduit Uses

Metal conduits can be used in any location and have high resistance to fire, heat, chemicals, moisture and impact. It is seen as a more attractive and professional choice compared to PVC, so it is often used in exposed areas. Using metal conduits is ideal for areas that may come into contact with harsh treatment.

PVC vs Metal Conduits: Key Differences

Both choices of material are great for electrical conduits, and both are durable and resistant to many elements. But what are the key differences in PVC vs metal conduits to make your decision on which to choose easier?

Installation

PVC can be cut, joined and installed with basic tools like a hacksaw and solvent cement. It is a lighter item than the metal variants, which can make installation even easier.

Metal conduits require more specialised tools for modification and installation. Galvanised steel, for instance, is far heavier and cumbersome, which could make it far harder. Flexible metal conduits do reduce this difficulty to a point.

As long as PVC is strong enough for your project, it is the far easier option for electrical conduit installation.

Environment & Performance

Although PVC can stand up to the harsher environment of outdoor installation, it is recommended to utilise a metal option instead.

PVC is a popular, affordable choice for indoor electrical installations due to its ease of installation. In contrast, metal conduits offer greater durability and physical protection, making them ideal for exposed indoor areas. For outdoor or underground applications, galvanised steel provides strong, impact-resistant protection against harsh conditions.

Selection

In the UK, PVC conduit is typically used for general-purpose internal wiring due to its lower cost, lighter weight, and ease of installation, making it a popular choice for residential and protected commercial environments.

On the other hand, metal conduit options, particularly galvanised steel, are preferred for industrial, outdoor, underground, or other demanding applications where greater physical durability, impact resistance and moisture protection are required. Flexible metal conduit options have worked to bridge the gap, but PVC is still the popular choice.

Cost

PVC as an electrical conduit material is significantly cheaper than its metal variants. It is also far lighter, so shipping costs will be reduced, as will the installation costs. Metal conduits require specialised tools to install and can take longer, which can lead to skyrocketing labour costs.

Metal conduits come with a higher up-front cost but can last far longer and stand up to more punishment than the PVC alternative.

Maintenance

PVC conduit is ideal for low-cost, low-maintenance installations, offering excellent resistance to moisture, chemicals and corrosion. It’s lightweight, easy to install and perfect for environments where rust and chemical exposure are concerns.

Metal conduit, while more expensive and requiring protective coatings to prevent rust, provides superior durability and impact resistance. It’s preferred in industrial, high-traffic, or high-heat areas for its strength and long-term reliability.

This is where the differences between the two are the closest. PVC is easier to maintain but requires more maintenance than metal.

Conclusion

Both metal conduits and PVC conduits are excellent choices for protecting and managing electrical cables. Your ideal choice will come down to the proposed application. For lighter-duty residential or indoor use with minimal chance of damage, PVC is the perfect choice. For more industrial and outdoor needs, a metallic choice would be a better and more substantial choice.

Conduits With Lenson Select

If you’re still deciding between PVC vs metal conduit options for your project, our expert team is here to assist. Don’t hesitate to get in touch with any questions. Whether you need advice or are ready to place an order, you can reach us at 0121 553 6699 or email us at sales@lenson-select.co.uk.