Container House Thermal Insulation Evaluation
The thermal insulation performance of container houses can be achieved through multi-layer composite structures, high-quality insulation materials, and thermal bridge interruption techniques. Measured data shows that their insulation efficiency can reach 1.8 times that of traditional brick-and-mortar walls, with minimal fluctuations in perceived temperature and strong adaptability across all seasons.
Multi-Layer Composite Structures and Material Selection
The core of thermal insulation in container houses lies in their multi-layer composite wall design. The outer layer typically uses anti-corrosion color-coated steel plates or galvanized steel plates for structural support and protection. The middle layer is filled with high-efficiency insulation materials such as polyurethane foam layers over 50mm thick, rock wool, or extruded polystyrene boards (XPS) to block heat conduction. The inner layer employs fire-resistant gypsum boards or decorative panels, working in conjunction with moisture-proof membranes to control humidity and temperature. For example, polyurethane rigid foam has a low thermal conductivity coefficient, offering the highest thermal resistance value for the same thickness, making it suitable for cold regions. Although rock wool has a slightly higher thermal conductivity coefficient, it possesses Class A fire resistance and is suitable for crowded places.
Thermal Bridge Interruption and Detail Handling
Thermal bridges are areas in the building envelope with locally lower thermal resistance, which can lead to rapid heat conduction. Container houses reduce the thermal bridge effect through the following measures:
- Install thermal insulation spacers between steel frames and metal panels to avoid direct metal contact forming heat pathways;
- Fill window and door openings with flexible insulation materials such as polyurethane foam sealant to block gaps;
- Adopt thermal break joint designs at the connection between the floor and walls to reduce heat conduction.
For example, the Apple Warehouse mobile house in Weifang, Shandong, employs sealing treatments and insulation filling techniques at frame connection joints and panel lap joints, significantly reducing the impact of thermal bridges on overall thermal insulation performance.
Measured Data and Perceived Temperature Differences
The national Technical Standard for Steel Structure Integrated Houses requires that the heat transfer coefficient of residential container walls be ≤0.45W/(㎡·K). Measured data shows that their insulation efficiency is 1.8 times that of traditional brick-and-mortar walls. Specifically, during summer noon, the temperature rise inside the container is 22 minutes slower than outside. In winter, with the container closed for 8 hours, the indoor temperature only drops by 1.3℃, with smooth temperature fluctuations and a more stable perceived temperature, free from stuffiness or sudden cold or heat. Some high-end products can control the indoor-outdoor temperature difference between 8-10℃ through double-layer composite walls of rock wool + extruded polystyrene boards combined with thermal break aluminum doors and windows, achieving warmth in winter and coolness in summer.
