Hometown Inspections

Is Your Home a Mold Trap?

In a wet, rainy climate, keeping your house dry and comfortable can be a challenge. But it’s not just about comfort. A home that traps moisture is a haven for mold, and leaks that go unchecked can cause structural damage as well as mold and mildew problems.

Is Your Home All Wet? Spotting Excessive Moisture

Most people are comfortable with a relative humidity between 25 and 50 percent. But keeping that level constant isn’t easy. Forced air heaters can dry out your environment, and everyday activities such as bathing, cooking, and dishwashing can add a lot of water vapor to the air. Even houseplants and fish tanks can add to the overall humidity.

Here are a few signs that your home may have too much moisture:

• Dampness and/or a moldy smell in basement
• Condensation, frost or ice on the inside of windows, warped sashes, moldy frames
• Damp areas, mold or mildew growth on interior walls and ceilings
• Cracks in exterior stucco, and peeling or blistering of exterior paint.
• Sweating water pipes
• Moisture, ice or frost in the attic space

Any amount of excess moisture can cause problems. It takes only four to six pints of water to raise the relative humidity of a 1,000 square foot house from 15 to 60 percent.

What Is Relative Humidity?

If you’ve ever been in cold weather with glasses on, then walked into a warm house, you might have noticed that your glasses fogged up. That’s because warm air can hold more moisture than cold air. Relative humidity is the ratio of actual humidity, as compared to the highest possible humidity, which depends on the temperature of the air. When relative humidity approaches 100 percent, it means that the air is totally saturated with water vapor. That’s when condensation can occur, leading to problems with mold, rot, and other moisture-related deterioration.

Under ordinary circumstances, proper ventilation should keep a house at the right humidity level. Learn more about the basics of good ventilation to see if your home is getting good air flow. If you think you have high humidity in your home, you can test the levels with a hygrometer. In order to prohibit mold growth in your home, you should make sure the relative humidity is 70 percent at the most.

Dry Up Your Act: How to Bring Down Humidity Levels

If you do have a moisture problem, it’s important to take action as soon as possible. Here are some tips for reducing the humidity and prevent condensation in your home:

• Vent appliances that produce moisture, such as clothes dryers and stoves
• Use exhaust fans or open windows when you cook or wash dishes
• Always run the bathroom fan when showering or running a hot bath
• Cover cold surfaces like cold water pipes with insulation.

In order to prevent leaks and moisture seepage, you should inspect the ground around your home. Make sure it slopes away from the building foundations, so water doesn’t pool around the walls. If you have a paved walkway or driveway next to your house, check for cracks in the pavement—they could be leading water toward your house and seeping it into your basement.

Rain barrels can cause problems if they don’t have overflow drainage. If you install rain barrels under your downspouts, make sure there is a way for excess water to flow away from the house. You might be surprised at how quickly a 40-gallon barrel can fill up, especially in an Oregon downpour.

Check your gutters to make sure they’re not blocked—once a year might not be enough, especially if you have tall trees near your house. Stopped up rain gutters channel water to places you don’t want it—like right next to your house. Install trays to channel water away from the foundation whenever possible.

Downspouts can also become clogged, so be sure to check them as well. Disconnect your downspouts if it makes sense to do so. Portland offers incentives for building owners in many areas to disconnect downspouts—learn more about the program. Not only will you alleviate the strain on the municipal sewer system, you’ll also ensure that they don’t get clogged, since you can always test the water flow.

More Ways to Prevent Mold

If you see condensation or moisture collecting on windows, dry the wet surface and try to determine the source of the water vapor. When water leaks or spills indoors, mop it up right away. If you let a wet or damp area sit for several days, mold and mildew may grow. Check your plumbing on a regular basis to make sure there are no leaks, and examine the drywall and wood surfaces in your basement to make sure they’re not damp or moldy.

If you think there might be a mold problem in your home, be sure to get a professional test—contact us to learn more about professional mold inspection services. And if you hire a mold remediation company to remove or repair moldy surfaces in your home, or you do it yourself, consider getting an independent mold inspection to make sure the mold has been safely removed. Even if it looks and smells fine, high levels of mold spores may still be present.