Complete Guide to Container House Insulation [2025 Updated]

Insulation is the key to transforming a shipping container into a truly livable home or workspace. Without proper insulation, container houses can become unbearably hot, freezing cold, or prone to condensation and mold. In this guide, we’ll explore why container house insulation is essential, what materials work best, and how Chengdong container houses ensure optimal thermal performance in all climates.

What is a Container House?

A container house is a type of modular building constructed using shipping containers or specially designed steel-structured units. These units are either repurposed from actual freight containers or custom-manufactured to container dimensions for ease of transport and assembly.

Container houses are popular in both temporary and semi-permanent applications due to their:

• Portability – movable, easy to transport and relocate

• Durability – built to withstand harsh environments

• Quick installation – on-site setup can be completed in hours or days

• Cost-efficiency – reusable, significantly cheaper than traditional buildings

They are widely used in construction camps, emergency housing, military camps, remote mining operations, and temporary offices or dormitories.

At CDPH (Chengdong Prefabricated Housing), container houses are factory-assembled, CE-certified, and engineered with fire resistance, thermal insulation, and windproof performance.

Why Insulation is Crucial for Container Houses

Shipping containers are made of steel, which conducts heat and cold very effectively. Without proper insulation:

• In hot climates, the container becomes unbearably hot.

• In cold climates, it loses heat rapidly.

• Condensation can build up on interior walls, leading to mold and rust.

So, insulation isn’t optional—it’s essential for energy efficiency, comfort, and durability.

Are Container Houses Insulated?

Yes — container houses can be insulated.

While standard shipping containers were not originally designed for living, most modern container houses, like prefabricated container houses from CDPH (Chengdong Prefabricated Housing), are engineered with built-in insulation systems to ensure comfort and energy efficiency for human occupancy.

Depending on the use case and climate, insulation materials may include:

• Rock wool

• Glass wool

• Polyurethane foam (PU)

• Expanded polystyrene (EPS)

  
  

These materials are applied in the walls, ceilings, and floors, helping to:

• Maintain indoor temperatures in hot or cold climates

• Reduce energy consumption for heating or cooling

• Improve soundproofing

• Prevent condensation and moisture buildup

Insulation Performance of Chengdong Container Houses

CDPH (Chengdong Prefabricated Housing) container houses are engineered to ensure optimal thermal performance in extreme climates ranging from -40°C to 40°C. Thermal calculations are conducted to determine appropriate insulation thickness, and the structural design incorporates thermal break technology to prevent condensation during use in harsh environments.

• Roof insulation: 100mm glass wool

• Floor insulation: 100mm glass wool (optional)

• Wall thickness options: 50mm, 75mm, 100mm, 150mm, 200mm

• Insulation material compliance: In accordance with GB/T 17795 – Glass Wool Products for Thermal Insulation in Buildings

These features ensure Chengdong container houses meet insulation requirements across diverse regions such as deserts, highlands, coastal areas, and cold zones, making them ideal for long-term deployment in global engineering and resource development projects.

CDPH (Chengdong Prefabricated Housing) also offers cold-resistant container houses—a modular building solution specifically engineered for use in extremely cold environments. These units are designed to perform reliably in regions where outdoor temperatures can drop as low as -30°C.

With the integration of enhanced insulation systems and additional heating solutions, the interior temperature can be maintained at a comfortable 20°C, ensuring year-round habitability even in harsh winter conditions.

Ways to Insulate a Container House

1. Spray Foam Insulation (Closed-Cell)

Liquid foam is sprayed directly onto the container’s interior or exterior walls, where it expands and hardens.

Pros:

• High R-value (excellent thermal resistance)

• Acts as an air and moisture barrier in one step

• Perfectly adheres to the curved or uneven surface of container walls

• Prevents condensation

Cons:

• High cost

• Professional installation recommended

• Not environmentally friendly due to chemical content

Best for: Harsh climates (extremely hot or cold), or high-performance, off-grid homes

2. Rigid Foam Board Insulation (XPS, EPS, or Polyiso)

Panels are cut to fit and glued to the walls and ceiling, then typically covered with drywall or plywood.

Pros:

• Easy DIY installation

• Good insulation at a moderate price

• Lightweight and moisture-resistant

• Can be used inside or outside

Cons:

• Needs to be carefully sealed at the edges

• Must be covered with fire-resistant materials

• Doesn’t offer soundproofing like other options

Best for: Moderate climates, DIY builds, or budget-conscious projects

3. Fiberglass Batt Insulation

Traditional insulation material placed between wooden or steel studs inside a framed wall.

Pros:

• Inexpensive and widely available

• Easy to cut and install with standard tools

• Works well when framed walls are already planned

Cons:

• Absorbs moisture—can lead to mold

• Poor air sealing unless combined with a vapor barrier

• Can irritate skin and lungs during installation

Best for: Dry climates, short-term housing, or interior-framed builds

4. Natural Insulation (Sheep Wool, Cotton, Hemp)

Rolls or batts of natural fiber placed between wall framing, similar to fiberglass.

Pros:

• Eco-friendly and sustainable

• Naturally mold-resistant and breathable

• Safe to handle—no protective gear needed

Cons:

• More expensive than synthetic options

• Lower R-value than closed-cell foam

• Limited availability in some regions

Best for: Environmentally-conscious builders or allergy-sensitive occupants

5. Structural Insulated Panels (SIPs) or PIR Insulated Panels

Pre-manufactured panels with insulation sandwiched between layers of board, replacing walls or roofs.

Pros:

• Extremely energy-efficient

• Quick and clean installation

• Load-bearing, so can simplify construction

Cons:

• Expensive

• Design must be carefully planned ahead of time

• Less flexibility if you want to modify layout later

Best for: Permanent homes, passive house design, or large container builds

Interior vs. Exterior Insulation

Best Practices for Container House Insulation

• Seal all gaps, joints, and seams before insulating

• Use a vapor barrier in humid climates

• Combine insulation with ventilation systems

• Don’t forget to insulate the roof and under the floor

• Follow local fire codes and building regulations

FAQs:

1. What are the features and benefits of foldable container houses?

The 20ft foldable container house manufactured by CDPH (Chengdong Prefabricated Housing) is a fully prefabricated model that can be packed into a compact, foldable box for easy transportation. Typically, one 40HQ container can accommodate 10 to 12 units.

Thanks to its integrated solid hinge system, the container house can be erected quickly and easily — two people can set up one unit in just 10 minutes with the help of a lifting crane.

The foldable container house is CE-certified, and features excellent safety, waterproofing, fire resistance, wind resistance, and thermal insulation.

Ideal for rapidly deploying dormitories and offices, this type of foldable container house is a cost-effective and reliable solution.

2. What is the best way to insulate a shipping container home?

The best way to insulate a shipping container home depends on your climate, budget, and use case. However, closed-cell polyurethane (PU) spray foam is often considered the most effective method. It creates a seamless moisture barrier, adheres directly to the metal surface, and provides excellent thermal resistance — ideal for both hot and cold climates.

Pro Tip: Combine quality insulation with good air sealing and proper ventilation for the best indoor comfort and energy efficiency.

3. Are Container Houses Fireproof?

Yes, container houses are fireproof. Learn more about the fire resistance of container houses in our detailed guide.

4. Is Cotton Insulation Good for Container Homes?

Yes, cotton insulation (often made from recycled denim) is eco-friendly, non-toxic, and provides decent thermal and acoustic insulation. However, it requires proper vapor barriers to prevent moisture buildup, which is especially important in metal structures like container homes.

5. Is Cork Insulation Good for Container Homes?

Yes, cork insulation is a natural, sustainable option that offers good thermal and sound insulation. It's mold-resistant and lightweight, making it suitable for container homes. However, it's typically more expensive and less common in large-scale prefab applications.

6. How long do container houses last?

On average, a well-built container house can last 15 to 25 years — or even longer — depending on the materials used, the environment it’s placed in, and how well it’s maintained. Learn more about the life span of container houses in our detailed guide.

7. What kind of insulation would you recommend for a 20′ shipping container being converted into a home or studio space?

For a 20′ shipping container converted into a home or studio, closed-cell spray foam insulation is highly recommended. It provides excellent thermal resistance, acts as a moisture barrier, and adheres well to the metal surface—ideal for small, enclosed spaces.

Alternatively, rigid foam boards (like PIR or XPS) are cost-effective and easy to install, while mineral wool or glass wool can offer strong fire and sound insulation if properly sealed.