A shikibuton can be part of a winter sleeping setup, but how warm you are depends on the floor, the room temperature, what is underneath you and the duvet above you, not on the shikibuton alone. On a cold floor, add an insulating layer under HIMARI or SORA, use a warm fitted cover, and choose a heavier kakebuton or duvet on top.
Layering from the floor up
- Floor: on tile, stone or concrete, lay a rug or insulating mat first; on wood, a moisture-absorbing pad.
- Shikibuton: the supportive sleeping layer.
- Fitted cover or sheet: a warmer fabric such as flannel in winter.
- Top layers: a heavier kakebuton or duvet, with a blanket added on the coldest nights.
Heating
The shikibuton can be laid directly over underfloor heating. If you use an electric blanket or heated underlay, follow its manufacturer’s instructions, and switch it off and let the bedding cool and dry before folding the shikibuton away. Heated rooms still produce moisture overnight, so keep airing it regularly.
HIMARI or SORA in a cold climate
Both have wool-blend filling. SORA 宙 has the higher proportion, a 50% premium wool blend, and a fuller approx. 12 cm loft, which adds natural warmth for those who feel the cold. HIMARI 日葵 has 25% wool and approx. 10 cm of loft, and is warm enough for most rooms when layered as above.