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Why is the Basement Humid in Summer and What Can I Do About It?

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Basements have a knack for getting wet and developing problems in summer. This is pretty normal, as it’s a time when humidity is at its peak. The air gets musty, carpets develop stains, wood decays or rots, and moisture droplets form on the cold basement floor and walls. Depending on the moisture problem, mold streaks may also form in the basement. All these undesirable effects will affect the quality of life indoors.

You can avert these issues by taming moisture and resolving anything that elevates basement humidity. If you’re not sure what to make of your basement or how to deal with moisture, read on and learn how moisture gets into this area and what you can do to stop it.

What Causes Basement Humidity?

Basement humidity in Cincinnati, OH, is a normal occurrence, so don’t agonize over it. The reason your basement gets wet or damp has to do with the fact that it lies below the grade or ground. Water can seep through and moisture can build up gradually, crossing the 60% mark. Water pipes can leak and ducts can let in moist air. The same goes for old basement windows. If the foundation has cracks and the basement is unfinished, the moisture situation could get worse.

Condensation should be your number one concern. It occurs when moist, warm air from the outside sweeps across cold surfaces. The result is moisture droplets that look like dew. You have to act fast to remedy it and other issues before they hurt your basement.

How Does Moisture Get into the Basement?

You probably know things that can make the basement wet, but do you know how moisture gets in? Here are the most common ways.

Vapor diffusion. Moisture can also move upward through porous foundation walls or floors as vapor and get into the drier parts of the basement. The amount of moisture that permeates depends on the porousness of the concrete and vapor pressure.

Structural cracks. Another way water gets into the basement is via cracks that form on the foundation

blocks or masonry structures. Soil settling and poorly joined floor joists are the culprits. Fixing cracks can eliminate this problem.

Capillary suction. This occurs when moist or waterlogged soils come into contact with concrete mass or walls of your basement. Water is drawn in through small pores in the concrete. When this happens, rings of dampness will form on the basement walls. Capillary suction is greatest in clay soils.

Air leakage. When warm air rises, it can induce a negative pressure on the basement, and in the process, draw up moist air through sump pits or foundation cracks and openings. Covering the sump pit and sealing the cracks helps resolve the problem.

How to Control Basement Humidity in Summer

Basement humidity shouldn’t cause you sleepless nights. As long as you know where it’s coming from, your contractor can apply the best fix. Let’s look at the most probable solutions.

1) Dehumidification. Even if the basement appears dry, water vapor can linger in the atmosphere for days or weeks. Get a hygrometer and measure humidity levels. If it’s higher than 60%, get a basement dehumidifier with a self-draining mechanism. It will suck out the vapor from the air, leaving it dry.

2) Interior drainage. Summer isn’t entirely dry and hot. There’ll be the occasional rain that can raise the humidity levels in the basement. To stop water from entering and collecting on the basement floor, get an interior drainage system like BasementGutter™. Combine yours with a sump pump, and you’ll never have to worry about flooding. When water gets in, it will be pumped outside.

3) Seal foundation cracks. As long as the cracks remain unattended, you can be sure water vapor and even liquid water will pass through them and get to your basement.

4) Leave windows shut. Summer heat can make the atmosphere hot and humid. Opening your basement windows won’t bring down the moisture levels. Instead, it will compound the problem. If you must open the windows, do so early in the morning or in the evening when the air is cooler. The reason is that cold air carries less moisture.

5) Don’t irrigate the garden. Using a sprinkler to irrigate your garden means a lot of water ends up where it’s not wanted. Some of it may get to the foundation walls. When the soil around it gets saturated, you can be sure some of the water will be drawn up through cracks.

6) Grade the yard. You may not have given this much thought, but how your yard slope affects basement dryness can heighten moisture levels or keep out water from the foundation.

7) Maintain gutters and downspouts. Clean, clog-free, functional gutters and downspouts can bolster your exterior waterproofing. You’ll want to make sure your drainage system collects rainwater and channels it away from the perimeter of your home.

Are you worried about what summer humidity could do to your basement? Schedule a free basement waterproofing inspection with the waterproofing experts at Ohio Basement Authority and get a complimentary quote plus solid recommendations to lock moisture out of the basement.

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Serving Greater Columbus, Cincinnati, Dayton, and Northern Kentucky

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1270 Hillsmith Dr.
Cincinnati, OH 45215

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Obetz, OH 43207

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Beavercreek, OH, 45440