Is the Interior of Container Houses Waterproof?

Container houses generally possess a certain degree of waterproofing capability, but their waterproof performance is influenced by multiple factors such as design, materials, and maintenance, and is not absolutely waterproof. The following provides an explanation from four aspects: waterproof design principles, performance standards, influencing factors, and maintenance recommendations.

I. Waterproof Design Principles
As temporary structures, foldable container houses achieve their waterproofing system through multi-dimensional design:

1. Waterproof Layer Installation: The roof employs high-performance waterproof membranes (such as SBS modified bitumen membranes or PVC waterproofing films, with a thickness of 1.5-2.5 millimeters). Walls use sealing strips or polyurethane foam to fill gaps, and wall panels (such as color-coated steel sheets) are coated with waterproof layers to form a physical barrier.
2. Drainage System Optimization: The roof is designed with a slope and equipped with drainage channels and downspouts to ensure rapid water diversion and prevent water accumulation and penetration.
3. Sealing Performance Enhancement: Connection points are sealed with sealing strips or sealants. Gaps between window and door frames and walls are filled with rubber gaskets or expanding foam to reduce pathways for rainwater intrusion.
4. Material Water Resistance: The disassembly and assembly structure selects corrosion-resistant and aging-resistant materials (such as galvanized steel sheets and aluminum alloys). The structural design considers the impact of long-term use and multiple disassemblies on waterproof performance.

II. Waterproof Performance Standards
High-quality container houses typically achieve a waterproof rating of IPX4 or higher, capable of withstanding a rainfall rate of 100 millimeters per hour. Their performance verification requires passing:

• Simulation Tests: Sprinkler equipment simulates continuous heavy rainfall for over 4 hours, with no leakage indoors considered qualified. Wind pressure resistance tests check waterproof stability under conditions of Level 10 winds accompanied by rain.
• Regulatory Requirements: Referencing the 'Technical Code for Building Waterproofing Engineering' (GB50345) and the 'Technical Standard for Container Houses' (CECS 334), no leakage should occur for at least 5 years under normal use conditions. In high-temperature, high-humidity, or coastal salt-spray environments, more weather-resistant materials such as ethylene propylene diene monomer (EPDM) rubber membranes are used.
• Maintenance to Extend Lifespan: Regular inspection of sealants and waterproof layers, with timely repair of damaged areas, can extend the waterproof lifespan to over 10 years.

III. Factors Influencing Waterproof Performance

1. Extreme Weather: Prolonged, high-intensity rainstorms may exceed design load capacities, leading to local leakage.
2. Material Aging: Waterproof membranes, sealants, and other materials may crack or detach over time, reducing waterproof effectiveness.
3. Construction Defects: Issues such as inadequate sealing during installation or blocked drainage systems may cause water leakage.
4. Environmental Corrosion: In coastal or high-humidity areas, salt spray or moisture may accelerate material corrosion, affecting waterproof performance.

IV. Maintenance and Improvement Recommendations

1. Regular Inspection: Inspect the roof and wall sealants and waterproof layers every six months, focusing on vulnerable areas such as joints and corners.
2. Timely Repair: When cracks or detachments are found, fill them with specialized sealants or waterproof coatings and cover with protective layers.
3. Enhancement Measures: In areas with frequent heavy rainfall, increase the thickness of the roof waterproof layer or install water diversion plates to improve drainage efficiency.
4. Emergency Preparedness: Equip with waterproof cloths, sandbags, and other materials for temporary sealing in case of sudden leakage, reducing indoor damage.