Thermal Insulation for Container Houses

The design and construction of thermally insulated container houses require comprehensive consideration of four aspects—material selection, structural optimization, door and window design, and detail treatment—to achieve efficient, energy-saving thermal insulation.

I. Selection of Thermal Insulation Materials

Material performance directly affects insulation effectiveness, so materials with low thermal conductivity and high durability should be prioritized. Common materials include:

• Expanded polystyrene board (EPS): Lower cost, thermal conductivity of about 0.038-0.042 W/(m·K), suitable for dry environments, but fire resistance is average.
• Polyurethane foam board (PU): Thermal conductivity as low as 0.022-0.028 W/(m·K), closed-cell structure with strong moisture resistance, often used in cold-chain containers, but relatively expensive.
• Rock wool board: Thermal conductivity of about 0.036-0.044 W/(m·K), Class A fire resistance, good sound absorption and noise reduction, suitable for high-temperature or high fire-resistance scenarios. Material thickness should be adjusted according to climate conditions; for example, cold regions are advised to use 50-100mm thick polyurethane boards.

II. Adding Thermal Insulation Layers

By adding insulation layers to block heat transfer paths, common approaches include:

• External insulation cladding: Install metal sandwich panels or integrated insulation-decoration panels on the container exterior to form a continuous insulation layer and reduce thermal bridging.
• Interior insulation boards: Lay rock wool or phenolic boards on the container interior walls, suitable for renovation projects, but moisture protection must be considered.
• Composite structure: Some designs adopt a composite structure of "container + studs + insulation layer + interior finish panels" to further improve insulation performance.

III. Optimization of Door and Window Systems

Doors and windows are primary channels for heat loss and should be improved through the following design measures:

• Glass selection: Use double or triple insulating glass (e.g., 5Low-E+12A+5 configuration) with warm-edge spacers to reduce the heat transfer coefficient to 1.5-2.0 W/(m²·K).
• Sealing treatment: Apply silicone sealant at window frame-to-wall connections, and install rubber weatherstrips on door gaps to reduce air infiltration.
• Shading design: External sunshades or Low-E glass that reflects part of solar radiation help reduce summer air-conditioning loads.

IV. Detail Treatment and Airtightness

• Joint sealing: Use staggered joints at insulation board seams and fill gaps with polyurethane foam adhesive.
• Structural connections: Use elastic sealant between container corner fittings and the insulation layer to prevent cracking caused by metal thermal expansion and contraction.
• Moisture protection: Install a vapor barrier (such as PE film) on the inner side of the insulation layer to prevent condensation from affecting insulation performance.

Through the above measures, thermally insulated container houses can achieve a K-value (heat transfer coefficient) below 0.5 W/(m²·K), meeting passive building standards and significantly reducing energy consumption.