Basement dehumidifiers and humidity control
Some basements never flood but always feel clammy. Keeping the humidity down protects stored belongings, framing and the air upstairs.
Basement walls and floors stay cool because they're surrounded by earth. On a muggy Southern Tier summer day, warm air that drifts into the basement drops its moisture on those cool surfaces, on cold water pipes, and on anything stored against an outside wall. Add moisture wicking up through the slab and through old stone or block, and you get a basement that smells musty even when the floor is dry.
How dry should a basement be?
The U.S. Environmental Protection Agency recommends keeping indoor relative humidity below 60 percent, ideally between 30 and 50 percent. A cheap digital humidity gauge will tell you where yours stands. If the basement reads above 60 percent for weeks in summer, mold has an easy time on cardboard, wood and the paper face of drywall.
What does a waterproofing company bring?
- Sizing. A small portable unit can run all day in a big, damp basement and still lose. Whole-basement dehumidifiers are built to keep working in cool air and move far more of it.
- Drainage. The unit can drain to a floor drain, into the sump pit or through a condensate pump, so no one is emptying a bucket twice a day.
- The source. If moisture is coming through the walls or floor, the company should say so instead of just selling a machine. A sealed sump lid, a wall membrane or better outside drainage can make the dehumidifier's job much smaller.
What can I do today?
- Clean gutters and extend downspouts several feet from the foundation
- Regrade soil so it slopes away from the house
- Make sure the dryer vents outdoors with a tight connection
- Move stored items into plastic bins, up off the floor and away from outside walls
- Dry anything that gets wet within 24 to 48 hours, which the EPA says generally prevents mold from growing
What affects the price?
- Basement size and how damp it stays
- Dehumidifier type and capacity
- How the unit drains, and whether a condensate pump is needed
- Any sump, wall or floor sealing done at the same time
Pricing comes from the waterproofing company after someone has been in the basement, looked at the walls, floor joint and sump, and walked the outside of the house. We don't quote prices, and nobody can give you an honest number over the phone before seeing where the water actually comes in.
Where we connect you with help
Common questions
Will a dehumidifier stop a leaking basement?
No. It pulls moisture out of the air, not water coming through a crack or floor joint. Fix the leak, then control the humidity.
Where should a basement dehumidifier drain?
To a floor drain, the sump pit, or a condensate pump that carries the water out. Ask how it will drain before it's installed.
Related services
More background: Broome County basement water guide.
Wet floor edge, a weeping crack, or a sump that runs all night?
Call and a Broome County waterproofing company will come find where the water is getting in.