Excessive humidity in your home can significantly damage drywall, windows, and the overall structure. It can also create an ideal environment for mold and mildew growth, which can be especially irritating for those with allergies. According to the Mayo Clinic the ideal humidity level for your home is between 45 to 50 percent RH (relative humidity).
A whole-house dehumidifier is the answer to overwhelming humidity. This article will answer questions and address concerns about finding and installing the best dehumidifier for your home.
- How do Whole House Dehumidifiers Work?
- How are Whole House Dehumidifiers Sized?
- How are Homes Classified for Dehumidification?
- Whole House Dehumidifier Sizing Chart
- How Much are Whole House Dehumidifiers?
- How Long do Whole House Dehumidifiers Last?
How do Whole House Dehumidifiers Work?
Typically, whole-house dehumidifiers fully duct into your home’s HVAC or furnace system. As moist air draws into the HVAC system from the return, it runs through the dehumidifier to remove the moisture before rereleasing into the supply to flow into your home as fresh, drier air.
You can operate these appliances using the onboard controller or wiring them into your home’s control system. The control system will automatically maintain the relative humidity setpoint.
How are Whole House Dehumidifiers Sized?
Dehumidifiers are sized by “pint capacity” or “moisture removal capacity,” indicating how many pints of moisture they can pull from the air daily. Other specifications you will likely see are “at AHAM” and “at Saturation,” which refer to the air quality conditions during machine tests.
- AHAM (Association of Home Appliance Manufacturers): With this rating, the dehumidifier tested at 80 degrees Fahrenheit and 60 percent RH for total pint capacity. Most manufacturers provide the recommended square footage for a dehumidifier at AHAM conditions.
- Saturation: A test conducted at 90 degrees Fahrenheit and 90 percent RH levels.
- Sealed Classification: The quality of your home's seals affects the airflow, so if your home is sealed poorly, you will need a larger dehumidifier.
How are Homes Classified?
While square footage is critical to determining the right dehumidifier, it’s also essential to know your well your home is sealed.
- Loosely Sealed: Usually older, these structures have minimal air sealing with foundations with imperfections or cracks.
- Moderately Sealed: These are usually newer or remodeled homes or buildings with some air sealing and undamaged foundations.
- Tightly Sealed: Most often new, these structures meet a recognized energy building standard such as LEED, Energy Star, or Passive House or have a confirmed air leakage of 3 ACH50 or less.
Most whole-house dehumidifiers can operate in temperatures as low as 40 degrees, so they can be installed in attics or basements, where most HVAC and furnace systems are located.
Whole House Dehumidifier Sizing Chart
Now that you know your home's square footage and classification, you can use the chart below to determine the size of the whole-house dehumidifier you need.
| Whole House Dehumidifier Sizing Chart | ||||
|---|---|---|---|---|
| Building Conditions | 70-80 pints | 75-100 pints | 100-155 pints | 155-225 pints |
| Loosely Sealed | up to 1,800 sq.ft. | up to 2,200 sq.ft. | up to 3,600 sq.ft. | up to 4,000 sq.ft. |
| Moderately Sealed | up to 2,200 sq.ft. | up to 2,600 sq.ft. | up to 3,200 sq.ft. | up to 4,000 sq.ft. |
| Tightly Sealed | up to 2,600 sq.ft. | up to 3,000 sq.ft. | up to 4,400 sq.ft. | up to 5,000 sq.ft. |
How Much are Whole House Dehumidifiers?
Of course, the price depends on the size of the unit needed. On average, whole-house dehumidifiers range in price from $1,350 for smaller homes up to 2,500 square feet to $4,600 for larger homes or office spaces up to 5,000 square feet.
How Long do Whole House Dehumidifiers Last?
Whole-house dehumidifiers from Santa Fe and Aprilaire are high-quality machines built for 10 to 15 years of reliable use. They include 5 or 6-year warranties and can feature fresh-air ventilation options.
Summary
A whole-house dehumidifier is designed to operate in tandem with your home’s HVAC or furnace system and can function in temperatures as low as 40 degrees F for installation in attics or basements. Based on the house's square footage and sealed classification, you can determine the correct size dehumidifier for your home.
Contact our Product Experts at 1 (800) 934-9194 or experts@sylvane.com for additional information and help sizing a dehumidifier for your home.
