For when it's too darned dry
Cold air can't hold as much water as warm air. So in many parts of the country, humidity is low in the winter, making the air in the house uncomfortably dry. Low humidity dries out mucous membranes, making you more susceptible to colds. It can make your eyes and skin itch, chap your lips, and irritate your throat and nasal passages. It can cause nosebleeds and aggravate asthma and sinusitis--not to mention the toll it can take on your furniture and musical instruments such as guitars and pianos.
Dryness can even boost your energy bill. The low humidity that you welcome in summer has the same cooling effect in the winter, when you don't want it. This may cause you to set the thermostat higher.
When your lips are chapped, your skin is flaking, and your house feels like the Sahara, it's time to consider a humidifier.
When shopping, look for
- Energy savings. Steam and "warm-mist" humidifiers use more energy than the ultrasonic, impeller, or evaporative types because they involve heating water. In-duct models generally use the least energy of any type.
- Easy-to-use controls and hydrostat. The humidifier should have a hydrostat, which automatically controls the humidity. Why? Because too much humidity can cause serious health problems for some people.
- The right size. Consider the area that needs to be dehumidified. If you have high ceilings, you should probably get a humidifier with a square-foot capacity that is higher than the actual square footage you wish to humidify.
- Easy maintenance. Unclean humidifiers can breed bacteria and mold that can aggravate irritations and allergic reactions. If you think you might tend to neglect the chores associated with keeping yours clean, get an easy-care model.
Some humidifiers can only cover 600 square feet, while "whole-house" models that can handle up to 5,000 square feet. Your options include:
- Tabletop. If you need to humidify a small area, tabletops are the lowest-priced choices. They can be easily moved, but require refilling and careful maintenance. They produce humidity using five basic methods:
- Vaporizers. The simplest type, these boil water to create steam, which kills fungi and bacteria that might otherwise live in the unit. But they are energy hogs and can tip over, especially if you have children or pets in the house.
- Misters. These use warm water, but not heated to a hazardous level. They also require much more energy than all but the steam vaporizer models.
- Sound waves. These generate a mist by using ultrasonic vibrations. Unfortunately, they can spew out white dust from minerals in the water and harbor unhealthy microorganisms. Filters, distilled water, and proper maintenance can solve both of these problems, however.
- Impellers. These models create a mist with a rapidly spinning disk. Like ultrasonic humidifiers, they can harbor dangerous microorganisms. They also may require filters and distilled water.
- Evaporators. Blowing air through a dampened wick or filter to circulate moisture, these usually have higher capacity and require less energy than steam or warm-mist models. But they need to be carefully maintained.
- Console. These are larger than the tabletops, with a higher capacity. They're also portable, but designed to sit on the floor. They need refilling and have the same maintenance requirements as the tabletop models. They usually use the energy-saving evaporative method.
- In-duct. If you have a hot-air furnace with a duct system, you can have a humidifier installed in the heating duct. These cost anywhere from $100 to $250, plus up to another $200 for installation. They require minimal maintenance, with a few filter changes each season, and never have to be filled by hand because they are plumbed directly to a home's water supply.
...to your health
The ideal humidity is about 45%. It will make your house comfortable for your entire household--and healthy for people with allergies or respiratory problems.
...to your wallet
Because a humidifier can protect furniture, wallpaper, musical instruments, and artwork from damage caused from parched air, the device can save on repair, restoration, and replacement costs.
...to the Earth
If a humidifier helps cut your use of energy for heating, it may reduce your emissions of global warming gases. And, of course, if it prevents damage, it saves resources.
Overdoing it. If you get a lot of condensation on your windows, you may have to settle for an indoor humidity below the ideal 45%. Even so, try to stay above 30%.
Test the humidity. Before you purchase a humidifier, make sure you actually need one by checking your home's humidity with a hygrometer. These are available for $10 to $20.