Storage Room

Originally, a storage room（納戶）referred to a space for storing clothes and other items inside the house. In real estate ads, it often describes rooms without windows or with very small windows. According to Building Standards Act, residential rooms must have windows that are at least one-seventh of the room’s floor area in size（Building Standards Act Articles 28, Section 1）. Recently, the term “Service Room” has also become common. There is not a clear difference between “Service Room” and “Storage Room（納戶）”. On floor plans, “S” means “Service Room”, and “N” means “Storage Room（納戶）”.