How’s your indoor humidity? The ideal indoor humidity is 20 to 60%, meaning that your air contains that much water vapor relative to the total it could hold at the temperature you have.

If it’s too low in winter, you can run into a lot of static electricity and dryness in your mucous membranes plus dry skin along with itching and chapping. Also, you can feel cold even though the actual temperature is satisfactory because your body moisture evaporates very quickly and cools you. And wood furniture and cabinets can dry out.

If your indoor humidity is too high, fogging and condensation can develop on and around your windows, and mold can develop in enclosed areas such as closets.

If your air is too dry and you have hot-air heating, you can add moisture most conveniently and efficiently by installing a

humidifier that automatically will introduce water from your household supply into the air ducts attached to your furnace. It will have a control (humidistat) that will maintain the relative humidity you choose to set. If you have hot-water heating, you can hang water pans on your radiators (they’ll need re-filling from time to time).

If your humidity is too high, turn on kitchen and bathroom exhaust fans, cook with covered pots and pans, take shorter and cooler showers and/or install a fresh air intake vent. Or just open a window for a few minutes to let some colder, drier air in. Be sure you have no humidifier running and (in the summer) use a dehumidifier.