A living room sits well at 20–22 °C, a bedroom at 17–20 °C, a bathroom at 22–24 °C. Humidity belongs between 40 and 60 %.
Below that band the air dries skin and airways. Above it, walls and corners grow mould. A hygrometer tells you which way to go: a humidifier in winter, a dehumidifier when the room stays wet.
