Dryer skin and hair, irritated nasal passages, dry throats, itchy eyes, and—zap!—static electricity are all signs of not enough humidity in your home. Besides increasing your risk for a respiratory illness, dry air is detrimental to wooden furniture, floors, and trim, which can crack and split.

Humidifiers can solve the dry-air problem. Ideally, indoor humidity should be between 30 and 50 percent. To determine the level in your home, purchase an indoor humidity monitor. (These are often included in home weather stations that also show the temperature.)

There are three types of humidifiers to choose from. The most common are tabletop humidifiers, inexpensive portable units that work best for single rooms. The small water tank requires daily refills and weekly disinfecting, plus some units are noisy, which is a concern if you’re buying one to use in a bedroom.

Console humidifiers are larger, multiroom units that are somewhat portable and often designed to look like a cabinet to fit into a room’s décor. The larger tank means fewer refills, but the units can be very noisy. Some create as much noise as a window air conditioner, plus they can increase your electric bill.

A whole-house humidifier also called an in-duct humidifier, sends moisture throughout the entire house via a forced-air heating system. This system requires professional installation. (Most heating and air conditioning companies can do the work.)

No matter what type of humidifier you choose, be sure to follow the manufacturer’s maintenance instructions to keep harmful bacteria from growing in the water tank and dispersing into the air.

There’s very little risk of having too much humidity indoors during the winter months, especially in newer homes with tight, energy-efficient construction. But a warning sign is condensation building up on the windows. Too much condensation can seep from the windows into walls and ceilings, potentially leading to peeling paint, damp insulation, mold, mildew, and rot.

There are a few alternate ways to increase your home’s humidity without a humidifier:

• Simmer a pot of water on your stovetop. Add cinnamon sticks, cloves, star anise, citrus peels, or dried herbs and flowers for a lovely fragrance. If you use a woodstove, this is a great place for a pot of water.

• Houseplants and vases of water also add humidity to a room.

• Place a bowl or pan of water over part of a heating vent, on top of a radiator, or near a heat source.

• After a bath, let the water remain in the tub until it is completely cool

• Open the bathroom door after a shower to let the steam into nearby rooms.

• Hang your laundry to dry instead of using the dryer.

• Purchase a tabletop fountain.