The Basics

How do I know if I need a dehumidifier?

Dehumidifiers are a great way to get rid of excess moisture in your home and prevent any issues that could be brought on by high humidity levels. Some of these issues include:

  • Mold
  • Musty smells
  • Warm, clammy conditions
  • Condensation on windows or other surfaces
  • Uneven floorboards

Ignoring the problems above can lead to allergic reactions, respiratory issues, or other health problems as well as lasting structural damage to your home. If you want to control humidity levels and keep excess moisture at bay, you should try a dehumidifier.

Where can I use a dehumidifier?

Dehumidifiers are usually placed in problem areas like basements, crawl spaces, laundry rooms, bathrooms, and any bedrooms or other areas that might have high humidity levels.

How do dehumidifiers work?

Dehumidifiers are fairly simple appliances that work by:

  • Drawing damp air into the unit
  • Cooling the damp air with a condenser to remove moisture
  • Collecting the removed moisture into a reservoir inside the dehumidifier
  • Using a fan to redistribute dry, dehumidified air into the room


What size dehumidifier do I need?

Dehumidifiers can be categorized by the amount of water they can remove from the air within a 24-hour period as well as by the size of the space they will be used in:

  • Small rooms (up to 500 sq. ft.) - For spaces like bathrooms or bedrooms
  • Medium rooms (up to 1,000 sq. ft.) - For spaces like dens or living rooms
  • Large rooms (up to 1,500 sq. ft.) - For spaces like basements, crawl spaces, or other excessively damp areas
  • Whole-house dehumidifiers (up to 3,000 sq. ft.) – For integrating into your home’s existing HVAC system

What is the ideal humidity level for my environment?

The ideal humidity level for homes is between 40-50%. If the relative humidity level rises above 50%, you can create an environment conducive to mold spores, dust mites, and bacteria. Conversely, a low humidity level below 30% can lead to an increase in colds, dry skin, and irritated respiratory passages, as well as structural damage such as cracked ceilings and separated wood floors.

What features should I look for in a dehumidifier?

When shopping for a dehumidifier, first look for the appropriate pint capacity and coverage area. Then, consider some of these other features:

  • Digital humidistat: Look for a dehumidifier with a digital humidistat for set-it-and-forget-it moisture control. It will automatically adjust to keep your room at the set humidity level.
  • Energy Star: Energy Star-qualified dehumidifiers remove the same amount of moisture as similarly sized dehumidifiers while using 10-20% less energy.
  • Internal condensate pump: The most convenient way to remove moisture is by purchasing a dehumidifier with an internal condensate pump. The pump automatically pushes moisture up and out of the units.

What is the difference between a dehumidifier with a pump versus one without a pump?

In a dehumidifier without a pump, a reservoir fills with water extracted from the air and must be manually emptied. A dehumidifier with a pump automatically pumps moisture out of the appliance through a tube that is connected to a sink or outside of a window. Because these pumps operate automatically, water can also be pumped out vertically.

How much does it cost to operate a dehumidifier?

The cost associated with operating your dehumidifier depends on the individual appliance, the amount of time the dehumidifier is operating each day, and your electricity rate. In general, you can expect to spend $5 to $30 each month on electricity costs. You can conserve energy by looking for an Energy Star-rated dehumidifier. You should also make sure to purchase a dehumidifier with a large enough capacity to handle your humidity problem. Purchasing a smaller, lower-priced dehumidifier can result in high energy costs if the appliance must run continuously to remove excess humidity.

How loud are dehumidifiers?

As with any fan-based appliance, the higher the fan setting, the greater a dehumidifier’s noise output will be. Dehumidifiers also use a compressor, which makes slightly more noise than a fan. When the compressor is operating, you should expect an increase in noise.

On lower settings, the noise from a dehumidifier is comparable to white noise. See the decibel chart below for reference:

Comparative Noise Levels for common indoor and outdoor sound levels are sown on a scale up to 110 decibels


Do dehumidifiers create heat?

A dehumidifier will add some heat to its immediate environment, though this varies greatly depending on the size of the dehumidifier and of the area it is operating in. The smaller the room, the more the air temperature will be raised, while in a large area the effect is usually not noticeable.

What is the lowest temperature a dehumidifier can operate in?

Most dehumidifiers can operate in temperatures as low as 41 degrees. See your unit’s specifications to double-check specific operating temperatures.