How To Look At A House

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What can I do to prevent mold problems in my home?

Saturday, October 6, 2018

Two Best Strategies for Mold Control

Moisture control and ventilation are the two prime mold-prevention strategies. First, stop moisture from getting in and, second, exhaust any moist air that is created in the home to the exterior right away. Most people think of water intrusion only in it’s most dramatic forms: a roof leak staining the ceiling or a puddle of water spreading across the floor from a leaking water pipe. But the slow and barely-noticed forms of water accumulation in your home can do just as much damage. 

    Cooking, bathing, heating with natural gas or propane, tiny  holes in an exterior walls that let in outdoor air, and even people breathing--all add gallons of water to the air in a home each day. Because mold requires a moist environment to grow, moisture-control is the most effective form of mold control. Here’s some places to check: 

•• Use the bathroom exhaust fans when showering and make sure they actually exhaust the air to the outside--that the ducts are not blocked or crimped, and don’t terminate in the attic.

•• If the hood fan over the range exhausts to the exterior (not recirculating), check to make sure that the air is actually blowing out at the termination point at the exterior wall or roof. If the range hood fan is recirculating, consider opening a window when cooking.

•• Clothes dryers produce and exhaust a tremendous amount of hot, moist air. Make sure the dryer duct isn’t damaged or clogged with lint, and verify that air is blowing out at the termination point. 

•• Check the caulking around the exterior doors and windows every four or five years, and repair any cracked or missing areas.

•• Check the caulking around bathtubs and showers, and retouch as necessary to keep a good seal.

•• Clean the gutters and downspouts each season, and keep them clear of debris. Downspouts should end at splash block or extensions that divert the water away from the base of the house. 

•• Poke your head up into the attic at least once a year to look around with a flashlight and sniff the air for any suspicious smells.

•• Adjust away from the walls any irrigation sprinklers that are spraying onto the house. 

•• Keep the condensate drain line from the air conditioning system flowing freely to a location away from the walls of the house. The terminations of the drain lines shown below are both too close to the house and obstructed by mulch. Flush the line at least once a year and check for any leaks at the pipe connections.

•• Make sure you know where the main water shut-off valve for your home is located, so you can turn off the water quickly in the event of a pipe leak.

   And when a water leak or spill does occur, clean it up promptly. Mold growth can begin with 48-hours on wet surfaces. For more on how mold and moisture can affect your home environment, click below to download the EPA guide for homeowners.

    Also, see our blog posts Should I buy a house with mold? and Why do new homes have more moisture and mold problems than older houses?

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Here’s links to a collection of our other blog posts about MOLD:

• Is mold contagious? Can mold spread to my home if there is a nearby house with mold?  

Can infrared thermal imaging find mold behind a wall?

 What is the right humidity level in a mobile home?

Who can clean up mold found during a home inspection in Florida?

How do I look for and find mold in my mobile home? 

• Why is there mold around the air conditioning vents? 

What can I do to prevent mold problems in my home?

Why is there a lead paint disclaimer in my real estate sales contract? 

How can I prevent mold in my Florida winter home when I'm gone for the summer? 

Should I use bleach to clean up mold?

• What should I do if mold is found during a home inspection?

      Visit our MOLD, LEAD AND OTHER CONTAMINANTS page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles. 

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