A humidifier adds moisture to a home’s dry air. While a small humidifier is ideal for bedrooms and nurseries, big rooms may need a larger one. Large humidifiers feature tanks capable of holding up to 4 gallons, which can release enough mist to fill a 4,000-square-foot area (sometimes a bit more than that), improving indoor air quality in every room of the house.
These large humidifiers are built as evaporators or ultrasonic units in both warm-mist and cool-mist options. This guide offers tips and identifies the options to consider when shopping for the best humidifier for a large room.
- BEST OVERALL: Levoit LV600HH Hybrid Ultrasonic Humidifier
- BEST BANG FOR THE BUCK: Everlasting Comfort Ultrasonic Cool Mist Humidifier
- BEST HIGH-CAPACITY: Aircare MA1201 Whole-House Console-Style Humidifier
- TECH PICK: Levoit Classic 300S Ultrasonic Smart Humidifier
- BEST DESIGN: Aircare EP9800 Whole-House Pedestal-Style Humidifier
- BEST WHOLE-HOUSE: Aprilaire 800 Whole-House Steam Humidifier
- BEST EFFICIENCY: Vornado EVDC500 Energy Smart Evaporative Humidifier
- BEST AIR PURIFIER COMBO: Sharp KC850U Air Purifier and Humidifier
- ALSO CONSIDER: Venta LW45 Original Evaporative Humidifier
How We Chose the Best Humidifiers for Large Rooms
In researching the most sought-after humidifiers for large rooms, we found that the best ones are usually defined by type, tank capacity, coverage area, settings, size, and other special features.
Evaporative and ultrasonic humidifiers are typically the most popular, thanks to their compact size, ample coverage area, and ease of use. Though less popular, whole-house humidifiers generate much more mist with their considerable tank sizes and abundant settings.
No matter the type, our list prioritizes cold- and warm-mist humidifiers that have 1.5- to 18-gallon tanks, providing 500 to 4,200 square feet of coverage. Many of our choices also include convenient settings, like automatic shutoff and multiple air speeds. Though some models are large and take up space, others are compact enough to keep on a nightstand or desk. Some select picks include dual-sensor technology, filterless operation, rotating disks, remote controls, smart-home connectivity, and digital control panels.
Our Top Picks
Our top picks include evaporative, whole-home, and ultrasonic humidifiers. The following models can emit a soothing mist that can span across large rooms, ranging from 500 to 4,000 square feet.
With an attractive design, various settings, and a 1.5-gallon tank capacity, this Levoit humidifier for large rooms is an excellent option for big spaces. The LV600HH is a hybrid model that can operate as a warm-mist or cool-mist humidifier. Its tank capacity is enough for 60 hours of use before needing a refill. With a maximum mist output of 500 milliliters per hour, this model can fill rooms that are between 430 and 753 square feet with moist air.
Users can adjust the mist output, humidistat, and automatic shutoff timer via the LV600HH model’s control panel or by using the convenient remote control. Other features include an aromatherapy box with absorption pads. It features a wide opening on the top for easy cleaning.
- Type: Ultrasonic
- Warm vs. cool mist: Both
- Tank capacity: 1.5 gallons
- Compatible square footage: 430 to 753 square feet
- Can provide a choice of either warm or cool mist for up to 50 hours
- Benefits from both a front control panel and an additional handheld remote
- The built-in aroma box allows relaxing aromatherapy oils to be added
- If this model is placed too close to a wall, the humidistat can be inaccurate
- Various faults have been reported, though that’s not uncommon with high sales volumes
Get the Levoit LV600HH humidifier for large rooms at Amazon, Lowe’s, or Macy’s.
Considered the best humidifier for bedroom use, the Everlasting Comfort cool-mist humidifier features a 1.5-gallon tank and a powerful fan to add moisture for up to 50 hours. This may be an inexpensive humidifier, but it delivers all the features anyone really needs. It’s best used as a small-room humidifier, suitable for increasing humidity in rooms measuring up to 500 square feet. An analog knob fine-tunes the humidifier’s mist output.
This cool-mist humidifier also features an essential oils compartment for aromatherapy. It lacks a built-in humidistat, though, requiring the user to monitor the humidity levels in the room to avoid introducing too much moisture to the space. Its auto-shutdown function can turn the unit off if the basin runs out of water.
- Type: Ultrasonic
- Warm vs. cool mist: Cool
- Tank capacity: 1.5 gallons
- Compatible square footage: 500 square feet
- Whisper Quiet technology makes this unit perfect for nightly bedroom use
- 1.5-gallon tank ensures 50 hours of continuous operation before it needs to be refilled
- Auto shutoff function prevents the humidifier from operating without water
- Lack of a built-in humidistat means adjustments have to be made manually
- Not effective when used for spaces larger than 500 square feet
Get the Everlasting Comfort humidifier for large rooms at Amazon, Newegg, or Everlasting Comfort.
With its 3.6-gallon tank, the Aircare MA1201 whole-house console-style evaporative humidifier produces enough water vapor to treat up to 3,600 square feet. Its built-in humidistat turns the unit off and on automatically, depending on the humidity levels in the home. The user can set it and forget it. A digital control panel with clearly labeled buttons helps users easily adjust the humidifier’s humidity levels and fan speed. It also shuts off automatically when the unit is empty, preventing the motor from burning out.
With its sturdy set of casters, users can roll this large cool-mist humidifier from room to room. At 20.5 inches tall and 21.5 inches wide, this is one of the larger humidifiers on the market.
- Type: Whole-house/evaporative
- Warm vs. cool mist: Cool
- Tank capacity: 3.6 gallons
- Compatible square footage: 3,600 square feet
- The digital control panel allows precise setting of humidity levels
- Has warning lights for auto shutoff, refill levels, and filter changes
- Can be set to adjust fan speed automatically, maintaining room’s humidity level
- Some users say the 3,600-square-foot coverage area claim is inaccurate
- A few users claim that the manual included with this item was incorrect
Get the Aircare MA1201 humidifier for large rooms at The Home Depot or Aircare.
Those who love high-tech gadgets may find the Classic 300S ultrasonic smart humidifier from Levoit to be the optimal choice. With a 1.58-gallon tank capacity, this pick is suitable for 215- to 505-square-foot rooms, distributing cool-mist air four times faster than other brands’ humidifiers. Smart connectivity through the VeSync app also allows owners to alter the humidity levels with their smartphone, though it does connect to Amazon Alexa and Google Assistant as well.
The included smart humidity sensor can trigger an auto mode to adjust moisture levels based on the room’s current condition or manually use the voice-command option when users’ hands are otherwise occupied.
Its small BPA-free construction is compact and easy to place anywhere and comes with an adjustable night light, an LED control panel, and operates at under 30 decibels of sound, making it perfect for bedrooms and nurseries. Need more? It can also act as an essential oil diffuser. The only downside to this particular model is that it needs frequent cleaning to maintain proper functionality.
- Type: Ultrasonic
- Warm vs. cool mist: Cool
- Tank capacity: 1.58 gallons
- Compatible square footage: 215 to 505 square feet
- Wi-Fi connectivity allows remote control and voice activation via Alexa or Google Assistant
- User-friendly features include 4 mist levels and a night light with 2 brightness settings
- One of the quietest humidifiers on the market at just 30 decibels
- Some functions are only available via the app, not from the machine’s control panel
- Several buyers have reported leaks that sometimes cause additional malfunctions
Get the Levoit classic humidifier for large rooms at Amazon or Levoit.
With its faux-wood panel sides and dark espresso stain finish, the Aircare EP9800 whole-house evaporative humidifier is the best cool mist humidifier in terms of design and reach, a bonus for those wanting to treat the air in a large room while still preserving the interior decor. This humidifier’s 3.5-gallon capacity is enough to treat an entire 2,400-square-foot home.
Measuring 27.3 inches tall by 18 inches wide, this large humidifier probably needs a permanent space in the home. Users can trade out the model’s replaceable tile top to match the room’s decor. The digital controls can quickly adjust the humidity level and the humidifier’s nine fan speeds. An automatic shutoff feature prevents the motor from burning out when the reservoir is empty.
- Type: Whole-house/evaporative
- Warm vs. cool mist: Cool
- Tank capacity: 3.5 gallons
- Compatible square footage: 2,400 square feet
- Digital panel offers 9 fan speeds for precise output control
- Has replaceable tile top and can be used as an additional side table
- Flip-out spout makes it easy to refill tank when necessary
- At maximum speed, the noise level may be considered quite loud to some
- Large size may not suit those looking for a portable humidifier
Get the Aircare EP9800 humidifier for large rooms at The Home Depot, Lowe’s, Grainger, or Aircare.
The Aprilaire 800 is a high-output steam humidifier that works in conjunction with a furnace and can provide precise humidity levels for homes of up to 6,200 square feet.
Special heating electrodes allow the use of ordinary tap water, unlike competitors that often require a purified supply. Once the digital humidistat is set, outdoor and indoor sensors ensure automatic maintenance of the desired humidity, so this is a set-and-forget device. Alarm lights on the main unit warn of problems with water supply, steam production, drain blockage, or when the humidifier needs to be serviced.
For homes without an existing HVAC system, a version is available that uses a wall-mounted fan situated in the main living space. Professional installation is strongly recommended for either model. However, the steam canister, which needs to be replaced every year, can be changed by the user.
- Type: Whole house
- Warm vs. cool mist: Unlisted
- Tank capacity: 34.6 gallons
- Compatible square footage: 6,200 square feet
- An exceptionally powerful humidifier with dual sensors for optimum performance
- Electrode technology runs on ordinary household water, so no filters are necessary
- Can be set to work continuously or only when the household furnace runs
- Requires that house has existing HVAC or a similar ducting system
- Professional installation necessary; technician is also needed to replace electrode wires every 3 years
Get the Aprilaire humidifier for large rooms at Amazon, Supply House, or Total Home Supply.
Vornado’s unique approach uses a combination of vortex airflow and a high-efficiency direct current (DC) motor. Rather than providing mist that might make surrounding areas damp, it humidifies the air as it circulates through the device. The result is efficient humidification of large rooms measuring up to 1,000 square feet while reducing electricity demands by as much as 90 percent compared to similar machines with common alternating current (AC) motors.
The Vornado EVDC500 has an attractive, contemporary design and weighs just 8.92 pounds, so it’s easy to move from one place to another. Two 1-gallon water tanks are easy to manage even when full and are a breeze to clean. The LED display indicates when the water level gets low, and the device will shut off automatically when empty. Multiple fan speeds allow for customized humidity settings, or it can run on auto.
- Type: Evaporative
- Warm vs. cool mist: Unspecified
- Tank capacity: 2 gallons
- Compatible square footage: 1,000 square feet
- The DC motor uses 90 percent less electricity than common AC equivalents
- The vortex action humidifies the whole room while minimizing energy consumption
- Easy-clean water tanks have a low-level indicator and auto shutoff when empty
- Some feel the device lacks the power to humidify the 1,000-square-foot coverage area effectively
- There have been reports of leaks or faults with the fan
Get the Vornado humidifier for large rooms at Amazon, The Home Depot, or Vornado.
The KC850U air purifier and humidifier from Sharp is a remarkable device that uses proprietary technology to attract particles from the air and filter them through a three-stage process. A high-efficiency particulate air filter removes 99.97 percent of particles down to just 0.3 microns.There is also a carbon filter that removes many common household odors.
The machine is capable of treating up to 1,230 square feet at one room change per hour. Three fan speeds and an auto setting allow the Sharp KC850U to be adjusted to suit the environment. An Energy Star certification ensures electricity consumption is kept to a minimum.
- Type: Unspecified
- Warm vs. cool mist: Unspecified
- Tank capacity: Unspecified
- Compatible square footage: 1,230 square feet
- Filters dust, pollen, smoke, and pet dander while also humidifying
- Energy Star certified for low power consumption and reduced emissions
- Set at low, the fan’s noise level is barely audible at 19 decibels
- The combination of purification and humidification comes at considerable cost
- Although filters should last at least 2 years, there are 3 that will eventually need to be changed
Get the Sharp humidifier for large rooms at Amazon, The Home Depot, or Best Buy.
Venta’s LW45 original evaporative humidifier has an unusual disk-stack mechanism that uses plain cold tap water to humidify an area of up to 600 square feet. With no need for filters, both maintenance requirements and running costs are reduced. Venta claims that humidifying in this way is more hygienic than mists and naturally reduces air pollutants and static. Aromatherapy oils can be added to the device to create a more relaxing environment.
The appearance is perhaps best described as utilitarian. There are simple, easy-to-use controls for on/off and three power levels. An auto shutoff prevents damage should the device run dry. At around 13 pounds, the Venta LW45 Original model is relatively portable, though a trolley with locking wheels is available as an accessory.
- Type: Evaporative
- Warm vs. cool mist: Cool
- Tank capacity: 3 gallons
- Compatible square footage: 600 square feet
- Uses a rotating-disk mechanism that is simple, effective, and low maintenance
- This mist-free model does not need filters and uses ordinary tap water
- Venta claims cold evaporation is more hygienic and also reduces pollutants and static
- Although undoubtedly efficient and robust, the price is significantly higher than most competitors
- Some users say this device’s gears show signs of deterioration after 1 year of use
Get the Venta humidifier for large rooms at Amazon, The Home Depot, Lowe’s, or Venta.
What to Consider When Choosing the Best Humidifier for Large Rooms
Before buying any humidifier in the hopes that it will be the right one for large rooms, shoppers will want to take time to learn the difference between each type on the market, especially the importance of tank capacity. In this section, we take a closer look at each type of humidifier along with other key features included in most high-capacity models.
Types of Humidifiers
Three types of humidifiers are typically designed to serve larger spaces: ultrasonic, evaporative, and whole house. Whole-house humidifiers are generally larger and best suited to supplying consistent humidity for the entire home, while ultrasonic and evaporation models are smaller and deliver mist to specific spaces. Here’s what buyers need to know about these three major types of humidifiers.
Ultrasonic humidifiers use a vibrating diaphragm that emits tiny water particles and a blower that distributes them, filling the air with moisture. This type of humidifier typically distributes its mist upward to give the particles enough time to vaporize before they come into contact with a hard surface.
Because ultrasonic humidifiers don’t rely on evaporation to create mist, they can typically send more moisture into the air than other types of humidifiers, making them ideal for large rooms and living areas. But if the water that’s evaporated using an ultrasonic humidifier contains minerals, this will leave residual white deposits on hard surfaces.
Evaporative humidifiers have a wick inside the basin that absorbs water. A blower collects dry air from the room where the humidifier is being used and blows this air across the wick to add moisture to the air before circulating it back into the room. Many evaporative humidifiers include a built-in humidistat that shuts the unit off automatically whenever the room’s air reaches a specific humidity level.
Generally speaking, evaporative humidifiers do not leave behind the white residue that other types of humidifiers (like the ultrasonic variety) typically create. But evaporative models do require periodic cleaning. That needs to be done to prevent the growth of bacteria inside the reservoir.
Whole-house humidifiers are connected to the ductwork of a house. Unlike ultrasonic and evaporative humidifiers that distribute mist from a single vent mounted on the humidifier, whole-house humidifiers work as part of the HVAC system, adding moisture to an entire home. Many of these humidifiers can also be connected to a house’s plumbing system, providing a limitless supply of water.
Some brands offer models that use a wall-mounted fan for houses that don’t have an HVAC system. Whether it works with the HVAC system or as a wall-mounted fan, professional installation is strongly recommended for any kind of whole-house humidifier.
Warm Mist vs. Cool Mist
A warm-mist humidifier adds moisture to the air by evaporating the water that is poured into its reservoir. The unit heats that water, causing it to vaporize. This type of humidifier is ideal during the cold winter months when colds and flu are rampant, causing all kinds of respiratory conditions. At these times, a warm-mist humidifier emits a soothing mist that makes breathing much easier.
By contrast, cool-mist humidifiers add water to the air by blowing dry air over a saturated wick. Unlike warm-mist humidifiers, the cool-mist variety does not use heat, making them ideal for warmer months and safe to use overnight or in children’s rooms.
Room Size and Tank Capacity
To serve a large room, a humidifier must be capable of producing a large quantity of mist. Most large-room models can emit enough water vapor to fill a space of at least 5,000 square feet, with whole-home models capable of producing enough mist to treat more than 4,000 square feet of space.
To handle this coverage, large humidifiers can hold up to 4 gallons of water, which gives them enough capacity to run for a day or more before requiring a refill. Some whole-home units attach directly to the home’s water lines, giving the humidifier a limitless supply of water.
Ease of Cleaning
Most humidifiers are easy to operate (simply fill the tank and turn on the unit) but are a bit trickier to maintain. It’s typically recommended to clean humidifiers once a week, so anyone looking to buy one will need to be prepared to set aside time to tackle this task. If mold grows inside the humidifier’s reservoir, the humidifier will distribute mold spores throughout the air, creating a health hazard.
Besides technology and capacity, the difference between a cheap humidifier and a more expensive model is often how the water tank is designed. The water tanks on more affordable models are sometimes impossible to access directly with a brush, which means it’s necessary to soak them regularly to prevent mold growth.
Because the wick stops releasing water vapor once the humidity in the room reaches a certain level, an evaporative humidifier can’t over-humidify the room. But an evaporative model can once its humidistat is turned on.
Unless it is turned off, an evaporative humidifier will release water particles into the air indefinitely (or until the water in its reservoir runs out). While convenient, this can create an issue if left unattended, causing moisture to form on the walls or even creating puddles on surfaces. To avoid this problem, many evaporative humidifiers feature a built-in humidistat that turns off the unit automatically when the air in the room reaches a certain humidity level.
Some humidifiers have features that enhance functionality. These features include controls that allow the user to adjust the humidifier’s fan speed or change the direction of the mist output. Higher-end models typically include a remote control.
Most humidifiers for large rooms include integrated timers that enable the user to set a shut-off time. They also feature an automatic shutoff that stops the unit from running when the reservoir is dry—this helps prevent motor burnout. UV filtration can kill bacteria that builds up in the reservoir over time. Some humidifiers include oil diffusers that can be used to release essential oils into the air.
Tips for Using a Humidifier for Large Rooms
Anyone looking to regulate humidity inside a home by using a humidifier will need to take time to learn how to work with its settings. The first setting they need to get familiar with is the one that controls the amount of moisture that is emitted into a room. It is recommended that this setting be kept under 50 percent to avoid the growth of mold and mildew.
Using distilled or purified water (instead of tap water) prevents unsavory particles from filtering through the humidifier and circulating in the air. Also, cleaning the humidifier regularly (at least once a week) can keep it functioning properly.
Here are a few more tips to consider:
- Before refilling the humidifier’s tank, the user should be sure the tank is completely dry and empty to avoid standing water and mold.
- If the humidifier requires a filter, the user needs to monitor when it needs to be replaced.
- The door to the room where the humidifier will be used should be left open to avoid over-humidifying the space.
- Warm-mist humidifiers that boil water can become hot to the touch. Those who live in a home with pets or animals will want to exercise caution.
This guide aimed to address everything shoppers need to know ahead of buying a humidifier, particularly the best ones for large rooms. Some may still have questions, though, so here are answers to some of the most commonly asked questions about these appliances.
Q. What size humidifier do you need for a large room?
Humidifiers with a 500- to 6,000-square-foot coverage range emit enough mist to cover a large room. These devices typically vary in size, but many are compact.
Q. What type of humidifier is most effective?
Each type of humidifier has its benefits, so it’s difficult to say that one is consistently more effective than another. In terms of energy efficiency, the Vornado humidifier for large rooms is hard to beat.
Q. What is the recommended indoor humidity level?
The ideal indoor humidity level for health and comfort is between 40 and 50 percent to help ease cold and allergy symptoms and make breathing easier while not making the air so humid that it promotes mold growth.
Q. Where should a humidifier be placed in a room?
The best place to position a humidifier is a few feet from the bed. This position allows the moist air to circulate enough to ease cold and allergy symptoms while not being so close that the user can breathe into it and distribute germs around the room.
Q. Can I run my humidifier all night?
It’s safe to leave a humidifier on all night if the unit has an automatic shutoff feature that turns off the unit when the reservoir is dry. An evaporative humidifier should also have a humidistat that turns off the unit after it reaches a certain humidity level to prevent the unit from over-humidifying the room.
Q. Can I use tap water in the humidifier?
While it’s OK to use tap water in a humidifier, distilled water is a better option. Tap water often has minerals in it that can leave deposits inside the humidifier or get released with the water vapor, leaving white dust on furniture around the room.
Q. Is a warm- or cool-mist humidifier better for sinuses?
If you have sensitive sinuses or are suffering from a cold or flu, using a cold- or warm-mist humidifier can help to ease sinus congestion. However, a warm-mist one may be a better option as it can soothe the sinuses more effectively.
Why Trust Bob Vila
Bob Vila has been America’s Handyman since 1979. As the host of beloved and groundbreaking TV series including “This Old House” and “Bob Vila’s Home Again,” he popularized and became synonymous with “do-it-yourself” home improvement.
Over the course of his decades-long career, Bob Vila has helped millions of people build, renovate, repair, and live better each day—a tradition that continues today with expert yet accessible home advice. The Bob Vila team distills need-to-know information into project tutorials, maintenance guides, tool 101s, and more. These home and garden experts then thoroughly research, vet, and recommend products that support homeowners, renters, DIYers, and professionals in their to-do lists.