Trailer Insulation for Reefers: Panel Foaming vs. Foam-In-Place

When it comes to refrigerated trailers, the quality of the foaming process for trailer insulation has a significant impact on thermal performance. Insulation isn’t just a technical step; it serves as a core component of trailer design that drives your thermal efficiency and reduces fuel usage, providing long-term durability. Whether you‘re transporting frozen food or pharmaceuticals, choosing the right trailer insulation method ensures your cargo stays protected in any climate. 

To decide which is right for your operation, it’s important to understand the options available. Two primary foaming processes dominate the market today: high-pressure panel foaming and foam-in-place (mandrel). Each approach shapes insulation performance, affects repairability, and influences your total cost of ownership. By taking a look at these differences, you can choose the solution that best aligns with your operational goals. 

Want an inside look? Check out this brief video to see how our science-backed paneling process delivers exceptional insulation.

Why Trailer Insulation Quality Matters

Insulation isn’t just a technical detail; it’s your primary defense against temperature fluctuations that threaten cargo integrity. When applied correctly and without voids, insulation maintains steady interior temperatures, reduces energy usage, and strengthens the long-term reliability of your trailers.

Given its critical role, understanding how different insulation methods perform is essential. One of the most advanced options is high-pressure panel foaming — a process designed for precision and consistency.

High-Pressure Panel Foaming: Built for Precision

The high-pressure panel foaming process focuses on consistency and control. Here are some key benefits:

• Modular Construction: Roofs, walls, and floors are foamed individually, providing uniform insulation for each panel.
• Computer-Controlled Injection: Advanced systems mix and inject polyurethane foam, eliminating guesswork and ensuring even distribution.
• Controlled Expansion: Foam expands under regulated conditions, producing flat, consistent layers free of cold spots or weak points.
• Temperature & Pressure Monitoring: Real-time oversight during the foaming process ensures every panel meets strict quality standards.
• Void-Free Results: This method is designed to prevent air pockets, so thermal performance isn’t compromised.
• Repairs: Repairs can be made in the traditional sheet/post spray method, but if the damage is severe, you also have the option to replace an entire side or roof. This replacement provides better thermal properties than spray foam and will look and perform as good as new.  

While panel foaming offers advantages for long-term performance, it’s not the only option available for your consideration.

Foam-In-Place: Fast and Familiar

The foam-in-place process is used across the industry and takes a different, more integrated approach. It works when foam is injected or sprayed directly into the trailer’s wall cavities, expanding to fill available space. As it cures, the foam bonds with the structure, adding insulation and support. Here are some key considerations:

• Faster Production: A single foaming step can insulate large areas, potentially speeding up manufacturing.
• Adhesion: Low pressure foam (mandrel process) can be used, which simplifies the trailer construction, but it’s harder to control the consistency of the foam density and cell structure.  These items are critical to get the best insulation values. High pressure foam (panel process) requires considerable effort. Each cavity must be precisely sealed to ensure the foam does not blow out, but it produces uniform, high-density insulation with strong adhesion.    
• Lower Initial Cost: Fewer manufacturing steps can translate to upfront savings.

However, it’s also important to consider the potential drawbacks. Here are a few things to consider:

• Risk of Voids: Since foam expands to fill space, complete coverage isn’t always guaranteed, leading to potential thermal weak spots.
• Inconsistent Results: Factors like temperature and humidity during application can affect how well the foam performs.
• Limited Repair Options: Even in the case of severe damage, the entire sidewall or roof must be rebuilt and foamed with less efficient spray foam, a labor-intensive process.  

Making the Strategic Call on Trailer Insulation

Insulation is a strategic choice that shapes your fleet’s overall performance. If you’re aiming for long-term efficiency, easier maintenance, and consistent thermal performance, panel foaming delivers a clear advantage. However, for projects where speed and initial cost take priority, foam-in-place may be the better fit, though it often comes with performance trade-offs.

No matter your priorities, our team at Great Dane is ready to support you with solutions that align with your operational goals so your fleet delivers safely, reliably, and efficiently, every time.

To take a look at how our reefer innovations offer exceptional performance start here.

Ready to maximize the performance of your refrigerated trailers? Contact our team today.