Saturday, November 16, 2024
35.0°F

Excessive rain can cause drainage problems

by ED Madan
| November 17, 2010 6:00 AM

With inclement weather come floods. Last week I received calls from local residents needing assistance because their basement or sunken living room flooded from excessive rain. Generally this situation happens because of hydrostatic pressure forcing water through the cracks or pores of the concrete foundation.

Hydrostatic pressure leaks require a little and a lot of work to solve the problem. The first thing that should be considered is the evaluation of your gutter system, down spouts, and surface grading layout around the home. These should be corrected first which may solve the problem. The idea is to force the water away from the foundation of the home. Then if moisture persists, proceed with an interior or exterior drainage system. Snow must be removed away from the side of the home, if not; as it melts it will migrate into the living envelope of the home.

Gutters, down spouts, and correct grading: many basement water problems can be solved by forcing the rainwater and surface drainage away from the home by using down spout extenders or splash blocks to redirect water away from the foundation. Sloping the grade may require hauling in fill dirt and placing it against the foundation sloped away from the home.

Installing an exterior drainage system at an existing building is the most costly of the water control approaches; however, it is the most effective. This requires digging up the area around the foundation and rebuilding it much like a new home installation.

As the water percolates down through the ground, it is captured by a porous pipe that direct the water away from the foundation to a drain system.

The most effective interior drainage system is a perforated drain pipe installed inside the perimeter of the footing. This requires removing and replacing concrete at the slab edge. By placing the drain beneath the slab, water can be direct to a sump pump system, which will pump out the collected water into a standard drainage system.

If a basement has moisture problems, covering it with any kind of wall finishing material or carpet will make things a lot worse. Wet carpet and drywall are excellent places for mold and fungus growth that can lead to health problems. Remember when relative humidity is about 50 percent in a home, there will be a problem with mold and fungus growth. The internal relative humidity for a home should be about 35 and 45 percent. If your home exceeds that mark, consider buying a small dehumidifier to remove excessive moisture. One good indication that you have excessive moisture is condensation build up on your windows.

If you would like to share a cleaning idea or concept with the reading audience, call Ed at NWES (255-2266), e-mail them to nwees@hughes.net or send them to Daily Bee, 310 Church St., Sandpoint, ID 83864, Attn: What Would Ed do?  For information about Ed, go online to www.nwees.com.

Copy written by Edmond E. Madan, certified indoor environmental professional, forensic, fire, flood, mold Inspection and remediation/restoration contractor. Ed is the president of Northwest Environmental Services, Inc.