Shipping Container Insulation: X-Bracket Exterior vs. Interior Panels – Which is Best for Your Build?
If you’re converting a shipping container into a livable space, workshop, or storage unit, choosing the right insulation method is crucial for comfort, energy efficiency, and longevity.
The versatility of the InSoFast EPS Insulation Panels and the new X-Bracket System, allow for both solutions to provide insulation on the interior or exterior of the shipping container. The InSoFast Sales Team is available to help you determine the best insulation solution for your container, but we see two popular choices selected for many containers when determining the best fit for your build.
Exterior Insulation
Insulating the exterior of a shipping container with The X-Bracket System and spray foam follows renowned building scientist, Joe Lsitburek’s “Perfect Wall” principles from Building Science Corporation. This method prioritizes placing insulation on the outside to create a seamless barrier against rain, air leaks, vapor, and heat transfer. Check out our latest installation video for X-Bracket.
“The perfect wall is an environmental separator—it has to keep the outside out and the inside in.” — Joe Lisitburek
There is a reason why our Shipping Container Panels are a top selling product for InSoFast. For those who prefer a more hands-on approach or have a mobile container, interior insulation panels offer a practical solution. These panels come with built-in framing, making them easier to install without specialized equipment. With the built-in stud framing attachment points, in each panel, you can easily finish the interior walls of your container and keep the exterior corrugated aesthetic.
This method is particularly well-suited for hot climates, where the primary concern is keeping heat out rather than preventing interior condensation. In southern states, insulating the interior can be effective since the goal is to block external heat from penetrating the living space. We have plenty of modifiers who regularly use ISF Panels in hot, humid, southern climates.
Blake Madgett of Containing Luxury – one of Florida’s premier container builders – consistently chooses InSoFast panels for their hot climate projects. The panels’ built-in framing and DIY-friendly design allow his crew to install them quickly and efficiently. See why a professional builder trusts this system in our installation videos featuring Blake’s projects.
Florida Builder Approved
One of the biggest advantages of interior panels is accessibility. Our panels are delivered directly from us to you. If you’re in a remote location or working on a tight budget, hiring a spray foam crew may not be feasible. With panels, you can handle the installation yourself, saving time and money.
However, while interior insulation does sacrifice some space, proper installation makes all the difference. Our YouTube install videos demonstrate how following factory specifications for air sealing – particularly at connection points – prevents moisture issues and ensures long-term performance.
Making the Right Choice for your Build
The best insulation method depends on your specific needs and InSoFast insulation solutions can provide exterior and interior benefits with both the EPS Insulation Panels and the X-Bracket System. If you prioritize durability, energy efficiency, and maximum interior space, exterior insulation is the clear winner. The X-Bracket with exterior spray foam is the best long-term solution, offering superior moisture control, energy efficiency, and space retention.
But if you need a simpler, DIY-friendly solution for a more mobile structure, and finished interior look, InSoFast panels may be the better fit. Interior panels provide a more accessible, and still high-performance option. This is especially true in hot climates where insulating the coldest wall is going to prevent the most condensation.
Have questions about insulating your shipping container?
Call our Sales Team at 888-501-7899 to talk more about your project.
