HIMARI and SORA have a 100% cotton outer fabric and wool-blend filling (25% wool in HIMARI, 50% premium wool blend in SORA), and both fibres take up moisture. That does not keep the bedding dry by itself or guarantee a cool night: use a separate washable sheet or cover, and let the moisture dry out between uses by lifting the shikibuton each morning.
Where the moisture goes
A sheet or fitted cover takes up much of the night’s moisture and can simply be washed. What reaches the shikibuton is released when it is folded or stood up in the morning and when it is aired. If a shikibuton stays down on the floor for days, that moisture has nowhere to go.
Summer and winter
- Warm months: use a light, breathable cotton or linen sheet and change it often.
- Cool months: a warmer fitted cover adds comfort; keep folding the shikibuton each morning, because winter bedding still collects moisture.
Habits that help
- Wash the sheet or cover weekly, or more often in hot weather.
- Fold or stand the shikibuton up every morning.
- Air both sides every one to two weeks in dry weather.