Reduce Basement Humidity

Quick Column Summary:

• How to reduce humidity in basement
• You may be doing everything right
• Damproof or waterproof foundations
• Run a humidifier

Tom Donohue, who lives up in Ontario, Canada, has a humid basement. He's not alone. Millions have this issue.

"How can I reduce humidity in my basement in the summer. I do not have cracks in my foundation or sitting water. The humidity level today is handled with a dehumidifier. Is there a better long term solution."

Here's my answer to Tom:

Tom, guess what? You're doing the best you can at this point until someone invents the magical sealer I've talked about for years.

If you have an older home that has NO foundation damproofing, or better yet waterproofing, and there's no vapor barrier under the concrete floor, you'll always be fighting water vapor that's pouring through the walls and floor into your basement.

All the new homes I built had DRY - not humid - basements because I made sure water vapor did NOT enter the space.

You also need to understand dew points. The walls and floor of your basement are cooler because they're in contact with the soil that stays cool up there.

Humid air that flows into your basement as the summer progresses can create condensation on the cooler walls and floors much like water droplets form on the outside of a glass of iced tea on your patio.

All you can do is run those dehumidifiers!