For a 1,500 square foot space, most homes need a 40–50 pint dehumidifier under typical conditions. If the area is damp, below grade, or in a humid climate, sizing up is usually the safer move.
Square footage gets you close. Moisture load makes the final call.
What Size Dehumidifier Covers 1500 Square Feet?
For most 1,500 sq ft areas:
- Mild humidity (50–60% RH): 40 pint unit
- Moderate humidity (60–70% RH): 45–50 pint unit
- Heavy humidity (over 70% RH or visible dampness): 50+ pint unit
If you do not know your current humidity level, measure it first.
Moisture Load Reminder
Square footage assumes average indoor conditions.
Moisture load increases when:
- The space includes basement area
- Outdoor humidity is high for much of the year
- Windows sweat regularly
- The area smells musty
- Air circulation is limited
If those conditions apply, lean toward the higher pint range.
If you are trying to determine whether your house is actually too damp, review the wet-side overview.
When to Size Up
Consider the larger end of the range if:
- Relative humidity stays above 65%
- The area includes multiple connected rooms
- You want quicker recovery after heavy rain or seasonal spikes
- Ceilings are higher than standard
- A smaller unit would run constantly
A slightly larger unit running steadily is usually quieter and more stable than an undersized unit that never shuts off.
Basement Adjustment
If the 1,500 sq ft includes basement space, assume higher moisture load.
Concrete walls and slabs release moisture over time. Limited airflow allows humidity to linger.
In most basement applications at this size, 50 pints is a practical starting point.
Climate Adjustment
In humid regions such as the Southeast, Gulf Coast, or coastal areas, indoor moisture load rises significantly.
In dry or high-altitude climates, the lower end of the sizing range may be adequate.
Climate matters more than marketing labels.
Ceiling Height Note
Standard sizing assumes 8-foot ceilings.
If ceilings are 9–10 feet or higher, you are conditioning more air volume. That generally pushes you toward the 50 pint range.
For a broader explanation of how sizing really works: How Big a Dehumidifier do i need?
Portable vs Whole-House
For a 1,500 sq ft open area, finished basement, or large living space, a portable unit is typically appropriate.
Whole-house dehumidifiers tie into ductwork and are sized based on the entire home’s air system, not just one zone.
Most homeowners at this size choose a portable Energy Star dehumidifier unit good for normal operation at about 1500 sg/ft.
Practical Recommendation
For most 1,500 sq ft spaces:
- Choose a 45–50 pint Energy Star unit
- Confirm actual humidity with a hygrometer
- Maintain indoor relative humidity around 50%
Avoid sizing at the bare minimum. Equipment that runs nonstop wears faster and struggles to stabilize conditions.
Reality Check
A dehumidifier manages airborne moisture. It does not solve foundation leaks, standing water, or drainage failures.
If humidity remains high even with continuous operation, the issue may be air infiltration or an active moisture source.
Dehumidifiers control conditions. They do not correct structural problems.