Checking for rain leaks

As I wrote earlier in the day, today is the traditional date of the start of rainy season. And as I wrote earlier in the week, rainy season started officially in the Greater Tokyo area a few days ago. That's what makes one of today's anniversaries, Rain Leak Inspection Day 雨漏り点検の日 so fitting.

"Rain Leak Inspection Day" is an anniversary of June 11th annually. The date was chosen exactly because June 11th often aligns with nyūbai, the aforementioned traditional calendar marker for the start of the rainy season. The anniversary was established in 1997 by the National Rain Leak Inspection Association, which is headquartered in Tanabe City, Wakayama Prefecture.

The purpose of this commemoration is simple but practical: encourage homeowners and building managers to check for potential leaks before heavy rains arrive, helping prevent costly damage and structural issues. The association themselves have a very interesting inspection method. They use a special liquid that glows blue under ultraviolet light, allowing inspectors to trace the exact path of water intrusion.