Plumbing and heating expert Richard Trethewey explains basement moisture control to Kevin O’Connor. After discussing some of the most common causes of wet basements and their consequences, Richard shows Kevin some methods for controlling them. Richard then explains how dehumidifiers work and how they may be the best option.
Wet Basement Woes are Hardly Universal
Believe it or not, only about 40 percent of homes in the U.S. have basements. However, of those homes that do have basements, 60 percent have moisture problems.
These problems may include rainwater not dispelling far enough from the eaves, groundwater soaking through the foundation, or moisture vapor making its way into the home. And despite not everyone having these issues, everyone who does dislikes them.
Why Wet Basements are a Problem
Make no mistake, wet basements can be a problem—especially with mold. To grow, mold needs the right temperature, moisture, and organic matter. All of these conditions exist in the average wet basement, and mold can grow, causing damage and health concerns.
When Grade is an Issue
Sometimes, the issue is that the grade pitches back toward the home. In these cases, there are two options: regrade the property or install French drains around the outside of the building. Both options will route the water to the yard and prevent it from soaking into the basement.
Also, adding downspout extensions to the gutters may allow the rainwater collecting on the roof to drain further away from the home. This can protect the foundation and prevent water from soaking the ground around the basement walls.
When It’s Groundwater or Vapor
Most of the materials used to construct foundations aren’t waterproof. Poured concrete, concrete blocks, and fieldstone are porous and will allow water into the basement. The option here is to seal the walls with hydraulic cement or epoxy paint. Another option is to use plastic sheeting to keep the moisture from making its way into the basement.
Another popular option in basement spaces is a floating subfloor with a plastic backing. These hard plastic backings have feet that hold them up off the floor and allow water to pass underneath them without soaking the USB on top.
If It’s Humidity
Not all humidity is bad (humans are most comfortable around 30 percent humidity). However, high humidity levels in a basement can be a problem. For these conditions, the best solution is often a dehumidifier.
Dehumidifiers are essentially low-powered air conditioners. They have cold coils on which moist air condenses. Once it condenses, it falls into a tank that the homeowner has to empty. They also have hose spouts that act as drains; some even come with pumps that push the condensed water out of the unit and into a drain.