10 Ways to Prevent Costly Mold Damage to Your Home

By: Karin Beuerlein, www.HouseLogic.com 

Fixing mold damage can be one of the most expensive repairs you'll ever perform on your home, so here's how to prevent it.

It is no wonder homeowners fear a mold diagnosis: Besides the health problems mold causes, the cost of an extensive mold remediation project can reach five figures.

You can't totally eliminate mold from your home no matter how vigilant you are, because mold spores are always present in indoor air, particularly in more humid areas of the country such as the Southeast and Northwest. What you can control by spending an hour or two inspecting key areas of your house and investing in a humidity monitor is the moisture that allows spores to colonize.


Eliminate clutter

1. Pare down your stuff. Clutter creates microclimates where humidity is higher than the ambient humidity in the room, says Jason Yost, owner of Solutions Indoor Environmental Consulting in Terre Haute, Ind. Mold develops because clutter blocks airflow, and your HVAC system can't process air properly.

2.  Don't obstruct air return and supply grilles with furniture or draperies. Surfaces adjacent to grilles cool to temperatures well below your thermostat setting and well below the dew point for the room, meaning condensation is likely.

Control the indoor climate

Mold problems often emerge in summer, when outside air tends to be humid. (If you have a window air conditioning unit, baseboard heating, or other localized devices and suspect you have moisture problems, consult an HVAC or mold inspection professional for guidance.)

3. Keep the thermostat set at a moderate level in summer. Set it too high, and the air conditioner won?t run often enough to dehumidify your air effectively; set it too low, and you create cold surfaces where water vapor can condense.

To maximize energy efficiency, most electric utilities recommend setting the thermostat around 78 degrees F; this setting is also optimal for preventing moisture problems.

4. Never keep windows or doors open while the air conditioner is on. This introduces humid outside air into a sharply cooler environment, which can cause condensation. When you go on vacation, don't bump the thermostat up to 85 degreesor, worse, turn the air conditioning off entirely. That tiny utility bill savings would be dwarfed by the cost of a mold remediation if your indoor air weren't sufficiently dehumidified. (Eighty degrees is recommended; if you have a window unit, leave it on at the lowest setting.)

5. Make sure your air-conditioning unit is properly sized for your house. Some HVAC contractors recommend oversized units for quick cooling, but this might remove less humidity from the air. Consult Energy Star to find out what size unit you really need.

6. Supplement an old air-conditioning unit that isn't removing as much moisture with a dehumidifier. 

Monitor moisture

To see if you need a dehumidifier, measure humidity -the amount of water vapor in the air compared with the total amount it can hold. Start with an under-$20 monitor from various online retailers, Yost says. More sophisticated and expensive models ranging from $45 to $300 have remote sensors that simultaneously track several rooms all over the house, which is useful if you have basements, crawl spaces, or other areas that you don't visit often.

An ideal indoor reading is between 35% and 50% relative humidity; in very humid climates in the height of summer, you may get readings closer to 55%. But if you reach 60% relative humidity, it's time to look for the source of the moisture. Above 70% relative humidity, certain species of mold can begin growing on surfaces even if water isn't visible.

7. If you get a high humidity reading, check your air conditioner first.

  • Is it set to the proper temperature?
  • Is it cycling on and off periodically?
  • Does it blow cold air when it reaches the set point?

8. Check that the condensate drain pipe (the narrow white pipe sticking out the side) is dripping regularly. If it isn't, the pipe is blocked, water may be accumulating inside the unit, or the unit isn't working correctly. If you suspect a problem, call your HVAC professional.

9. If the air conditioner isn't the issue, look for signs

10. If you have a crawl space, make sure you have a plastic vapor barrier covering the dirt floor and that it's intact. Moisture below the house affects the humidity indoors by infiltrating unsealed penetration points, such as where electrical conduits and plumbing enter the house. Water can even diffuse through plywood and finished flooring and you won't necessarily see wet spots when this happens.

Find a qualified pro

If you can't find the moisture problem on your own, or you aren't sure how to correct a problem you do find, it's a good idea to call a home inspector or indoor air quality consultant. Look for credentials from a respected industry organization, such as the American Society of Home Inspectors or the Indoor Air Quality Association. A house call will likely run $250 or more.

Keep in mind the mold field is largely unregulated, so there are few industry norms for pricing.

Mold and insurance

Mold remediation isn't necessarily covered by homeowners insurance, which typically pays only if the problem results from a sudden emergency already covered on your policy, such as a burst pipe. Insurance usually doesn't pay if the problem results from deferred maintenance or floodwaters (unless you have flood insurance).

Water emergencies

A note about emergency situations: If you have a flood or a leaking or burst pipe, act immediately to remove the water and run a dehumidifier don't wait for an insurance adjuster, inspector, or water extraction/mold remediation company to arrive. But take photos or video of any damage for your insurer.

The main thing to remember is to monitor moisture before problems develop and if something seems wrong, don't hesitate to call for professional help.

Karin Beuerlein has covered home improvement and green living topics extensively for HGTV.com, FineLiving.com, and FrontDoor.com. In more than a decade of freelancing, she has also written for dozens of national and regional publications, including Better Homes & Gardens and the Chicago Tribune. She and her husband started married life by remodeling the house they were living in. They still have both the marriage and the house, no small feat.


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