Basement dehumidifiers and humidity control
Some basements never flood but always feel clammy. Bringing the humidity down protects stored belongings, framing and the air upstairs.
A damp basement and a wet basement aren't the same problem. In a wet one, water comes in as liquid through a crack or the floor joint. In a damp one, the floor stays dry, but the air carries so much moisture that boxes go soft, tools rust and the whole space smells like an old cellar. Chemung valley summers are warm and humid, and when that air drifts downstairs and meets walls and floors chilled by the surrounding soil, it condenses, the same way a cold glass sweats on a porch in July. Vapor wicking through the slab and through stone or block walls adds more.
What humidity level should I aim for?
The U.S. Environmental Protection Agency recommends keeping indoor relative humidity below 60 percent, and ideally somewhere between 30 and 50 percent. Set an inexpensive digital hygrometer on a shelf for a week in summer. Readings that sit above 60 percent for long stretches give mold a foothold on cardboard, lumber, carpet and drywall paper.
Why not just buy a dehumidifier at the hardware store?
Sometimes that's enough. But small portable units are built for a single room at living-room temperatures. In a large, cool basement they can run nonstop, freeze up their coils and still lose ground, and someone has to empty the tank. A waterproofing company typically brings:
- A unit sized to the space, often a whole-basement model designed to keep working in cooler air and to move much more of it.
- Hands-off drainage to a floor drain, the sump pit or a small condensate pump that lifts the water outside.
- A look at the source. If moisture is coming through the walls or slab, a sealed sump cover, a wall membrane or better outdoor drainage can shrink the load. A good company says so instead of only selling equipment.
What helps right away?
- Clear the gutters and add downspout extensions that carry water well away from the house
- Build up soil along the foundation so it slopes outward
- Check that the dryer vent duct is connected tightly and exhausts outdoors
- Store belongings in plastic totes on shelves, not cardboard on the floor
- Dry anything that gets wet within 24 to 48 hours, which the EPA says generally prevents mold
What affects the price?
- Basement square footage and how much moisture it holds
- The type and capacity of the dehumidifier
- The drainage setup, including any condensate pump
- Sump, wall or floor sealing done in the same visit
Prices come from the waterproofing company once someone has stood in your basement, checked the walls, the floor joint and the sump, and looked at where roof and yard water goes outside. We don't quote prices, and an honest number can't be given over the phone before anyone has seen the water's path.
Where we connect you with help
Common questions
Will a dehumidifier stop a leaking basement?
No. A dehumidifier dries the air; it does nothing for liquid water coming through a crack or up at the floor joint. Stop the leak first, then manage what's left in the air.
Where should a basement dehumidifier drain?
Ideally somewhere it never needs attention: a floor drain, the sump pit, or a condensate pump piped outdoors. Settle the drainage plan before the unit goes in.
Related services
More background: Chemung County basement water guide.
Water at the base of the wall, a crack that drips, or a sump you don't trust?
Call and a Chemung County waterproofing company will come trace where the water is getting in.