Water Accumulation in Container Houses

Water accumulation in container houses is primarily related to extreme rainfall, joint seams, and window/door frame sealing issues.

Extreme rainfall as a direct cause: On the night of September 8, 2026, some areas in Nagoya experienced an hourly rainfall of 104.5 millimeters, setting a new historical record for local observations. The sudden heavy rainfall created strong surface runoff, continuously impacting the external structure of container houses and exceeding their normal drainage capacity, significantly increasing the risk of water accumulation.

Joint seam leakage as a critical pathway: Container houses are assembled from multiple standard containers, leaving structural gaps at the joints. Under extreme rainfall conditions, water seeps vertically or horizontally along these joint seams, forming 'linear seepage channels'. For example, during the Nagoya incident, water directly infiltrated indoor spaces through the joint seams, causing ankle-deep water accumulation in ground-floor rooms and soaking beds and belongings.

Window/door frame sealing failure exacerbates water ingress: Poorly sealed connections between window/door frames and the container body become vulnerable points for water infiltration. During heavy rain, water may pour in along the edges of window/door frames or directly enter through ventilation openings. Reports on social media from athletes about 'water ingress through ventilation openings and wall seepage' exemplify this issue, where rapid water accumulation in confined spaces disrupts normal activities.

Design limitations amplify disaster impacts: Container houses inherently have limited space, and their drainage systems are typically designed for normal rainfall conditions. When faced with historic extreme weather events, their existing drainage capacity becomes inadequate, and the lack of secondary waterproofing measures indoors (such as floor drains or water barriers) prevents timely water discharge, further worsening internal flooding.

Improvement recommendations: To address these issues, optimize the waterproofing of joint seams (e.g., using rubber seals or waterproof glue), enhance the sealing performance of window/door frames, and install indoor drainage slopes and emergency drainage devices. Additionally, under extreme weather warnings, relocate important items in advance to minimize losses.