Polycarbonate vs steel enclosures: which should you choose?

In industrial and commercial environments, enclosures do far more than simply house components. They protect sensitive equipment, ensure electrical safety, maintain compliance and help extend the lifespan of critical systems.

When specifying an enclosure, material choice is one of the most important decisions. Two of the most widely used options are polycarbonate and steel - both offering excellent protection, but suited to very different environments.

So how do you decide which is right for your application?

Why enclosure material matters

The material of an enclosure directly affects:

• Mechanical strength
• Resistance to corrosion and chemicals
• Electrical insulation
• Installation requirements
• Long-term durability
• Overall project cost

Choosing the wrong material can lead to premature failure, unnecessary expense or compliance issues. Understanding the differences between polycarbonate and steel ensures the enclosure performs reliably in its intended environment.

For more clarification on which enclosure suits best, read our full user's guide here

Polycarbonate enclosures: lightweight, versatile protection

Polycarbonate enclosures are widely used across automation, electrical control, telecommunications and general industrial installations. They're engineered plastics designed to offer strong impact resistance while remaining lightweight and electrically insulating.

Key advantages

1. Lightweight and easy to install

Polycarbonate enclosures are significantly lighter than metal alternatives. This simplifies handling, mounting and transportation - particularly in wall-mounted or pole-mounted applications.

2. Natural electrical insulation

As a non-conductive material, polycarbonate provides inherent electrical insulation. This reduces the need for additional grounding considerations and can simplify system design.

3. Corrosion resistance

Polycarbonate does not rust and performs well in damp or moderately corrosive environments. Many variants are also resistant to common industrial chemicals.

4. Cost-effective solution

In many applications, polycarbonate offers a lower upfront cost compared to steel, making it attractive for budget-sensitive projects or large-scale rollouts.

5. Strong ingress protection

High-quality polycarbonate enclosures are available with IP65, IP66 or higher ratings, providing excellent protection against dust and water ingress.

Considerations

• Lower temperature tolerance compared to steel
• Not ideal for extremely harsh mechanical environments
• Prolonged UV exposure requires UV-stabilised variants

For control panels, automation systems and outdoor electrical installations, polycarbonate often delivers the right balance of durability, insulation and value.

Steel enclosures: strong and economical

Steel enclosures are widely used in industrial and commercial settings where mechanical strength and cost-effectiveness are important. They are commonly specified in manufacturing, facilities management and electrical distribution systems.

Key advantages

1. Exceptional mechanical strength

Steel offers superior structural integrity, making it suitable for industrial environments with potential impact or heavy components.

2. Cost-effective durability

Plain steel is generally less expensive than stainless steel while still providing strong protection for indoor or covered environments.

3. Long service life (with protection)

When properly coated or painted, steel enclosures can withstand moderate environmental exposure and maintain structural integrity over time.

4. Suitable for larger installations

Steel is often preferred for large electrical cabinets, switchgear or control panels due to its strength and rigidity.

Considerations

• Susceptible to rust in wet or outdoor environments without proper coating
• Requires grounding due to electrical conductivity/li>
• Heavier and more challenging to install than polycarbonate/li>
• Modifications on site (cutting/drilling) are more labor-intensive/li>

Steel enclosures are ideal for indoor industrial applications, dry environments or locations where mechanical strength and cost savings are priorities.

Comparing performance by application

Instead of asking which material is “better,” it’s more useful to consider where each performs best.

Cost vs lifetime value

Steel enclosures are generally cheaper upfront, but in environments where corrosion is an issue, they may require repainting or additional protective measures. Polycarbonate, while sometimes slightly more expensive initially, often delivers a longer effective lifespan outdoors or in humid conditions.

Choosing the right material depends on:

• Environmental exposure
• Mechanical risk
• Compliance requirements
• Installation constraints
• Expected lifespan

Which enclosure material is right for you?

As a general guide:

Final thoughts

There is no universal “best” enclosure material - only the best fit for your application. Both polycarbonate and steel offer excellent protection when correctly specified.

By understanding the environmental demands, compliance needs and lifecycle expectations of your project, you can select an enclosure that ensures long-term performance, safety and reliability.

Which enclosure will you choose?