Temperature fluctuations can lead to expensive cargo damage that impacts your bottom line. Learning how to insulate a shipping container properly can save you a lot of headaches and money. Check out this guide to find out how to insulate a shipping container to prepare for intermodal shipping.
There are several regulatory and industry standards for insulating containers on rail, road, and sea legs, including ISO 1496-2, ATP, and FDA guidelines for perishables.
Cargo must be kept within the acceptable temperature range depending on the type of products you’re shipping. Room temperature is 59–77° F, refrigerated is 36–46° F, and frozen is -4° F.
Relative humidity (RH) levels also have to be kept within certain thresholds to prevent mold, corrosion, and cargo damage.
Stable internal temperatures reduce spoilage rates, protect sensitive electronics, and preserve the potency of pharmaceuticals. Using insulation also reduces heating and cooling costs, leading to reduced fuel costs and a smaller carbon footprint.
Insulation further reduces costs by reducing product losses, decreasing downtime for container repairs, and lowering the frequency and cost of insurance claims.
Closed-cell spray foam adheres directly to the walls of the shipping container, filling the grooves and creating a seamless vapor barrier. Closed-cell spray foam typically often has an R value exceeding R-6/in, while the commonly used rigid panels range from R-4/in to R-6/in.
Spray foam also adds stiffness which can be a benefit. However, rigid panels are easier to remove and replace.
Multi-layer reflective foil minimizes radiant heat transfer to maintain stable temperatures, especially on sun-facing walls. Combining foil with foam or bulk materials allows you to block convection and radiation.
Foil layers are also beneficial because they’re lightweight and thin, preserving the interior volume of your container.
R-value is the resistance a material has to conductive heat flow, with higher R-values being better in extreme climates. The combined R-value of a shipping container includes the walls and any additional insulating layers.
It’s important to note that R-value has diminishing returns. While higher R-value is generally better, there’s a point where extra R-value adds little benefit compared to its cost and weight.
Start with a detailed scan for rust spots, weld imperfections, door frame gaps, and roof seams that may be susceptible to moisture. Use marine-grade sealants and specialized tapes that are rated for significant temperature swings and exposure to saltwater to seal gaps.
Power wash or sandblast the container to remove old paint, grease, and corrosion until you’re working with a bare metal surface. Use a high-adhesion epoxy or zinc-rich primer to ensure the foam or panel has a strong bond.
You can also use liquid moisture barriers like bitumen or polyurethane membranes to create a moisture-resistant barrier before insulation goes in. This helps prevent damage caused by extreme temperature swings and humidity.
When you’re insulating a shipping container, it’s important that there are no gaps in insulation. You can prevent gaps by precisely measuring and cutting your insulation to make sure you’re getting even coverage throughout your container. Account for corrugations on sidewalls, door pocket recesses, and corner castings that can affect the accuracy of your measurement.
Before applying spray foam, make sure you have protective clothing, a full respirator, and adequate ventilation. Use a specialized spray gun that mixes the resin and catalyst to create the foam as you’re spraying it. Maintain a consistent thickness to avoid over-expansion.
Rigid panels can be attached to the walls of shipping containers using insulation anchors with neoprene washers. Fasteners should be spaced out about 12–16”. Use adhesive backing or contact glue to ensure the panels stay in place, especially on ceilings and vertical walls.
Use closed-cell spray foam or low-modulus silicone to seal small gaps. Panel seams should be sealed with metal-reinforced tape. Gaskets or foam collars around pipes and electrical conduits can help maintain the vapor barrier.
Temcore liners, thermal blankets, and pallet covers help maintain stable temperatures during shipping. These products are made from multiple layers of reflective and insulating materials, providing protection against extreme temperature swings.
Temcore Max pallet covers provide even better protection against extreme temperatures as they’re capable of holding temperatures to within 1 degree per hour.
Temcore covers are insulated barriers that are designed to fit over palletized goods, providing another layer of protection in addition to the container liner. These covers are easy to install and reusable, making them a simple eco-friendly option.
There are countless real-world examples of Temcore products in action. Suppliers and manufacturers who deal with food, pharmaceuticals, chemicals, electronics, and health and beauty products rely on our Temcore series to maintain stable temperatures when it matters most.
For extremely sensitive cargo, combining Temcore container liners with Temcore Max pallet covers provides maximum protection.
Temperature swings aren’t the only issue in global shipping. Moisture damage can cost you a fortune, so don’t forget to account for condensation and other potential moisture risks. Using desiccants and temperature stabilization solutions can help you cover all your bases.
Extreme environments call for extreme insulation, so make sure you choose insulation with an appropriate R-value based on the environment.
Steel walls expand and contract, which can cause rigid panels without expansion joints to crack and seals to fail.
For tropical routes, it’s generally recommended to aim for an insulation thickness of 3–4”.
You can retrofit insulation on used containers, but the container must be properly prepared to ensure the insulation adheres properly.
Thick layers of insulation can increase the weight and reduce the volume of shipping containers, which can lower your payload capacity by a small amount.
Reusable products like the Temcore series are an excellent choice if you’re looking for eco-friendly insulation for a shipping container.
Insulation should be inspected to ensure containers are properly protected during transit. You can install remote data loggers to receive real-time temperature updates.
Cargo damage can cost you a fortune, so it’s important to know how to insulate a shipping container. Using a combination of spray foam and other methods can help you protect sensitive cargo like food, pharmaceuticals, chemicals, and beauty products.
The Temcore series from Eurolog Packing Group is specifically designed to mitigate extreme temperatures, with Temcore Max covers capable of holding temperatures to within 1 degree per hour. Contact us to learn more about the Temcore series or get a quote for your next shipment.
Sandra Malouf is the President of Eurolog Packing Group and has spent her career focused on Industrial Packaging. With a proven track record of helping businesses avoid supply chain disruptions, Sandra’s visionary leadership elevates the industry. She’s committed to developing sustainable practices and continues to shape the future of industrial packaging by listening to the customer and offering unique solutions applicable to various industries across the world. The company’s main focus is temperature stabilization and moisture damage prevention in exports affected by extreme variations in global temperatures.
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