Value Village ／ Everyday know-how
This answer is a draft. It stays unpublished until legal review and source verification are complete.
The switch by the bathroom door in a Japanese home often has three settings — ventilate, dry, heat — and the fan runs for hours a day. It is not extravagance: the bathroom is the wettest room in a humid country, and in many homes it doubles as the laundry drying room.
| Function | What it does | When |
|---|---|---|
| Ventilate (換気) | Exhausts humid air | During bathing and 1–2 h after, or 24 h on low (mandated in homes built since 2003) |
| Dry (乾燥) | Warm air plus exhaust | Laundry drying: 2–3 h for a load hung on the bathroom rail; also to dry the room fast in the rainy season |
| Heat (暖房) | Warms the room before bathing | Winter, 10–15 min before a bath — the anti-heat-shock measure for older people (see the bath safety article) |
| Cool (涼風) | Fan only | Summer bathing |
| Cost | Ventilate: about ¥1 per hour; dry: ¥30–60 per load (heater type) | Cheaper than a tumble dryer for a small load; slower |
[Verify] Running costs vary by unit; the 2003 ventilation requirement with MLIT; NITE fan incidents.
Ventilation costs about ¥1 an hour and prevents the mould that costs a weekend to remove. Leave it running after baths; leave 24-hour units on.
That moves the moisture into the hallway and bedrooms — the source of condensation elsewhere. Door closed, fan on.
It is a sealed, ventilated, heated room with a pole — the best drying room in a Japanese flat, and the standard rainy-season method.
Warming the bathroom before a winter bath is the main preventive measure against the blood-pressure shock behind bath deaths (see that article). Ten minutes before an older person bathes.
Monthly filter cleaning; a clogged fan is quieter, weaker and, in heater units, a documented fire cause.
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https://www.mlit.go.jp/jutakukentiku/build/sickhouse.html
https://www.nite.go.jp/jiko/chuikanki/
https://www.caa.go.jp/policies/policy/consumer_safety/caution/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
Always follow the instructions on any product you use, and never mix cleaning products. If you rent your home, check with your landlord before making any changes.
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