The shikibuton can withstand underfloor-heating temperatures and be laid directly over it. Leave temperature to the surrounding bedding: in winter add a warmer fitted cover, a heavier kake futon, or an insulating layer; in summer switch to a cooling-fabric cover or a light summer quilt, alongside air conditioning or a fan.
If you are comparing Japanese futon care with a conventional mattress, focus on airflow, dryness, regular turning, and the right cover; these habits help the shikibuton keep its shape and comfort.
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