Value Village ／ Everyday know-how
This answer is a draft. It stays unpublished until legal review and source verification are complete.
A Japanese bath holds about 200 litres, and since the family washes before getting in, the water is clean enough to reuse. Most washing machines sold in Japan have a hose to draw from the bath. To visitors this sounds unhygienic; the numbers and the rules explain it.
| Item | Detail |
|---|---|
| Bath volume | about 180–220 L for a standard tub |
| Washing machine intake | 50–100 L per load for a top-loader; machines have a bath-water pump hose (furomizu pump) |
| Which cycle | Wash cycle only; rinse with tap water — this is the manufacturers' and government advice |
| When | Same evening or next morning; bacteria increase in warm standing water over 24 hours |
| Not for | Baby clothes, underwear if someone is ill, towels you want odour-free |
| Bath additives | Check the additive's label — some (with sulphur or milky agents) say "not for laundry"; many say "OK for wash cycle, not rinse" |
| Other uses | Toilet flushing (bucket), floor washing, watering plants (if no additives), emergency reserve (see the water-storage article) |
| Savings | 50–100 L per load; about ¥15–30 per load in water and sewer charges at Tokyo rates |
[Verify] Water-saving figures with the Tokyo Waterworks Bureau; bacterial data with consumer-testing reports (e.g. Kokusen); additive guidance on product labels.
The family washes before entering; the water is warm, soap-free and lightly used. It is used for the wash, not the rinse, and the rinse is tap water.
The rinse is tap water so no residue or odour remains. Wash-only is the rule from manufacturers, waterworks and consumer bodies.
Bacteria multiply in warm standing water; use it the same evening or the next morning, then drain and clean the tub.
Some additives stain fabric or damage the pump. Read the additive's label for a laundry statement; many list it explicitly.
50–100 L per load, every day, for a family is 20–35 m³ a year — a meaningful share of household water. And the warm wash cleans better.
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https://www.waterworks.metro.tokyo.lg.jp/kurashi/setsusui/
https://www.jema-net.or.jp/
https://www.hokeniryo.metro.tokyo.lg.jp/kankyo/
⚠️ 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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