Insulation of a shipping container

Insulating shipping containers is often necessary to ensure appropriate thermal conditions for the transported cargo. This can be achieved in several ways, but the most commonly used methods include insulation with polyurethane foam or mineral wool mats (e.g., mineral wool, fiberglass). Both methods offer good thermal insulation but have different properties suited for various applications. What is shipping container insulation? What properties does an insulated shipping container have? What and when to insulate a shipping container with? We'll answer these questions in today's article.

Table of Contents

• Introduction
• What can be used to insulate a shipping container?
• How does the insulation process work?
• Benefits of Container Insulation
• What is the heat transfer coefficient?
• Summary

In this article, we will present:

• How to insulate a shipping container and the benefits it generates
• The heat coefficient, i.e., the measure to guide you when insulating a container
• How the insulation process of a container goes - we will explain each stage of such action

What can be used to insulate a shipping container?

Insulating a shipping container is a process that involves adding an insulation layer to the container's internal walls, ceiling, and floor to ensure better temperature control inside and protect against moisture. There are many materials that can be used to insulate shipping containers, and the choice depends on various factors, such as the container's application (different applications may require a 20 container, another 40 container), budget, and user preferences. Here are some of the most popular insulation materials used for shipping container insulation:

• Polyurethane Foam: This is a very popular insulation material often used in shipping containers. Polyurethane foam has a high R-value (insulation measure), is moisture-resistant, and can be sprayed directly onto the container walls, creating a tight insulation layer.
• Mineral Wool: This is another popular insulation material often used in shipping containers. Mineral wool is easy to use, has a good R-value, is non-combustible, and has excellent soundproofing properties.
• Polystyrene Boards: These are lightweight and easy-to-use insulation boards often used in shipping containers. They have a good R-value and are relatively inexpensive, but they are not as moisture-resistant as polyurethane foam.
• Spray Foam Insulation: This form of insulation is sprayed onto the container walls, creating a tight insulation layer. It is an effective solution but may require specialized equipment to apply it to the container walls.
• Reflective Insulation (e.g., aluminum foil): This type of insulation works by reflecting heat instead of absorbing it. It can be used alone or in combination with other types of insulation.

The best choice of insulation method depends primarily on the specific needs and expectations. It's also important to remember proper installation and the use of appropriate vapor barriers to ensure effective and durable insulation of the shipping container.

How does the insulation process of a container work?

Insulating the walls of a container is a process that can be carried out in various ways depending on the chosen insulation material and expected results. However, this process usually includes the following steps:

1. Preparing the container walls: The first step is usually to clean and prepare the container walls. This may involve removing any dirt, rust, or paint that could affect the adhesion of the insulation material.
2. Frame installation: Next, when using insulation in the form of mats (e.g., mineral wool), a frame of wood or metal is installed to which the insulation will be attached. The frame should be mounted so that the insulation is in contact with the container walls but does not protrude beyond the wall edges.
3. Insulation installation: Then, the insulation material is cut to the right size and mounted on the frame. If polyurethane foam is used, it is sprayed directly onto the container walls. Once dry, the foam forms a solid, tight insulation layer.
4. Vapor barrier installation: If using insulation in mat form, a vapor barrier is applied over it to prevent water condensation in the insulation.
5. Wall panel installation: Finally, wall panels (e.g., gypsum board, wood, or metal) are applied over the insulation and vapor barrier, which are fixed to the frame.
6. Sealing: The last step is to seal any gaps and openings to ensure that the entire structure is airtight and there are no thermal bridges.

This is a general description of the process, but the detailed steps may vary depending on the specific conditions, requirements, and materials used.

Benefits of Container Insulation

Insulating a container brings many benefits that directly impact energy efficiency, comfort of use, and the durability of the container:

• Comfort of Use: Insulation improves the comfort of using the container by maintaining a

constant temperature inside, regardless of external conditions. This allows for the proper selection of cargo that must meet specific thermal requirements.

• Protection Against Moisture: Proper insulation and vapor barrier prevent condensation, which helps protect the container and its contents against moisture and potential damage.
• Noise Reduction: Insulation can also contribute to reducing noise levels, which is particularly important when the container is used in a noisy environment, and the cargo inside is sensitive to sound.
• Increased Durability of the Container: Thanks to insulation, the container is better protected against external factors, which contributes to extending its lifespan.

To illustrate the used insulation material and its properties in relation to price and fire resistance, a table was created that depicts the above relationships.

What is the heat transfer coefficient?

The heat transfer coefficient, often denoted as U, measures a material's ability to conduct heat. It is a key concept in material sciences and building physics, especially in the field of thermal insulation.

The U-value is the inverse of the R-value, which measures a material's insulation. The U-value is expressed in units of W/(m²·K), meaning watts per square meter per Kelvin. The lower the U-value, the better the material's insulation, meaning it conducts less heat.

In practice, the U-value is often used to assess the thermal performance of windows, doors, walls, and other elements. It determines how quickly heat penetrates the entire structure, taking into account all layers and the air through which the heat must pass. This coefficient allows for precise calculation of heating and cooling requirements for insulated shipping containers.

Summary

Choosing the right insulation material for warming up a container, such as polyurethane foam, mineral wool, or polystyrene boards, is crucial, considering both thermal efficiency and costs. It's important to properly prepare the container for insulation - the container should be clean, dry, and free of rust. During insulation installation, it's necessary to avoid gaps and cracks that could lead to heat loss and moisture problems. Proper vapor barrier and ventilation system are essential elements of effective container insulation.

If you're unsure how to approach the task, it's always worth consulting professionals in the field of container services. If you have more questions or would like to learn more about insulating shipping containers, do not hesitate to contact us. We're here to assist you at every stage of the shipping container insulation process.