Whether you’re cleaning up after a flood or trying to combat excessive, damp weather in your region, using one of the best dehumidifiers can help prevent mold and mildew growth. In addition, they can keep the air inside your home at a healthy humidity level. But how long does a dehumidifier take to dry out a room?
According to experts, it depends on several important factors, including the room size and humidity level. Find out more about using a dehumidifier to decrease the moisture level in your home, and how long it takes. Here's what the experts say.
How long does a dehumidifier take to dry out a room?
The exact time it takes a dehumidifier to dry out a room depends on the room size and the humidity level. “An HVAC-integrated dehumidifier works continuously to stabilize humidity levels across the home," explains Brad Roberson, president of Aire Serv, a Neighborly company. "Depending on the room size, humidity level, and unit capacity, a portable dehumidifier can typically dry out a room in about 6 to 12 hours.”
If you’re removing water from your home following a water leak or flood, expect the dehumidifier to take longer to work. Sometimes, it can take up to 72 hours to fully dry out a room.
The best way to ensure the dehumidifier has completely dried out your room is to carefully monitor humidity levels. Keep running the dehumidifier until humidity levels are back to normal. Even if the room looks and feels dry, the humidity levels may be higher than recommended, so monitoring those levels matters.
When do you need to use a dehumidifier?
There are several common signs that you might need to use a dehumidifier to dry out a room, including:
- A musty smell
- Excessive condensation
- Peeling paint
- The presence of mold or mildew
- After a water leak or a basement flood
In some areas that experience high humidity, you might need to use a dehumidifier more often — especially if you or a home resident suffers from allergies or asthma. High-humidity environments are a haven for dust mites, mold, and other factors that can worsen your symptoms.
How can I make my dehumidifier work faster?
Dehumidifiers will take several hours to dry out a room, regardless of what you do. However, there are several steps you can take to make a dehumidifier work faster.
“To make the dehumidifier work faster, close doors and windows, improve air circulation with fans, place a portable dehumidifier near the moisture source, and ensure proper maintenance has been done on the dehumidifier to increase efficiency,” recommends Roberson. The more you can get the air to circulate around the room, the faster it will dry.
Ensure correct positioning
As Roberson mentioned, the positioning of the dehumidifier is crucial in drying out the room quickly. After you’ve determined the source of the moisture, place the dehumidifier in that area so it can get to work quickly.
Not putting it in the correct location can increase the total drying time—and placing it too close to walls, furniture, or other potential blockages can hinder its functionality.
Use the correct size
You might think that any dehumidifier will dry out your room, but choosing the wrong size can lengthen the process considerably. Before you buy or rent a dehumidifier, check that it’s the appropriate size.
“An HVAC service professional can recommend the best dehumidification system based on the size of the home, HVAC capacity region, and individual preferences,” adds Roberson.
Increase air circulation
A dehumidifier works best when air is circulating freely. Portable fans can increase air circulation, helping the dehumidifier dry out the room more quickly. Closing doors and windows can also speed up the process because it keeps the circulating air in the affected room.
Maintain the dehumidifier
Proper dehumidifier maintenance helps it work to the best of its ability. Check the water level in the drip pan and empty it regularly—especially when you’re drying out an excessively damp or humid room.
Also, dust the outside of the dehumidifier every few weeks to prevent dirt buildup that can limit its functionality.
Select the correct humidity level
The U.S. Environmental Protection Agency (EPA) recommends an ideal indoor relative humidity (RH) level of 30% to 50%, with humidity not exceeding 60%. When using a dehumidifier to dry out a room, check that the machine’s settings are set to the correct RH level, which will ensure that the affected room is dried out to a healthy level.
How should I choose the right size dehumidifier?
Dehumidifiers come in various sizes, ranging from 10-pint to 60-pint, and the one you choose will affect the length of time it’ll take to dry out a room. But how can you choose the right size for your home and situation?
As Roberson explains, it depends on the type of dehumidifier you use, as well as the room size. “For portable dehumidifiers, match the unit’s capacity, which is measured in pints per day, to the room size and moisture level,” he says. “For small rooms up to 500 square feet, a unit that removes 20 to 30 pints of moisture works well, while large areas over 1,000 square feet would need a dehumidifier that removes around 50 to 70 pints each day. This could vary in areas with higher levels of sustained humidity.”
Use the following table to estimate the dehumidifier size you need for your space.
Room size | Recommended dehumidifier size |
400 square feet | 20- to 30-pint |
600 square feet | 25- to 40-pint |
800 square feet | 35- to 50-pint |
1,200 square feet | 50- to 60-pint |
If you opt to install a whole-home dehumidifier, you can expect it to work much faster. “For whole-home dehumidifiers, sizes range from 50 to 100-plus pints per day,” Roberson explains. However, whole-home dehumidifiers are much more costly than portable ones, so consider the return on investment before putting down any money.
A dehumidifier is a must-have appliance if you live in a damp region or frequently experience flooding or water leaks. It can help dry out a slightly damp room in around 6 to 12 hours or remove moisture following a water leak or flood in 72 hours or less. However, it’s essential to choose the right size dehumidifier and use it correctly to maximize its efficiency.
More from Tom's Guide
