There exists a "growing" environmental problem caused by energy efficiency and moisture. It's mold -- both hidden and in plain sight -- in and on walls, ceilings and carpets and any porous material that can absorb moisture and hold it until mold spores begin to grow. Why are we hearing about this more than ever before? Because more homes today are sealed airtight. When small water leaks occur in a roof or somewhere in a home's structure and go undetected for a period of time, wet insulation and wallboard become breeding grounds for mold. To put mold on hold, reduce interior moisture and humidity levels with good ventilation and a dehumidifier, if needed. Catch and repair leaks early. Condensation creates moisture problems, too. Watch for any signs of mold and act quickly to correct and prevent it. Besides being unsightly, it's a health hazard. And that's the On The House tip for today.