Q: No matter how well we clean our house, we keep finding some mold and mildew in the closets, under the sinks and elsewhere. I asked the guy at our hardware store about this and he said it was a common problem caused by energy- efficiency measures in today’s homes. Is he right about that?
A: File this one under the urban legends category. I hear it every so often too, but having discussed the idea with many energy experts over the years, I’m convinced that this isn’t the case at all. In fact, energy-efficient homes usually improve indoor air quality and cut down on the growth of mold and mildew.
However, this can be considered an energy issue because heat and damp conditions in a home can lead to mold and mildew problems. Maybe you’re not setting the air conditioner in summer low enough to get rid of indoor humidity. Maybe you’re not using exhaust fans in the bathroom that get rid of moisture after showering or bathing. Do you have good ventilation in the home to control the humidity level?
Rather than cause indoor air quality problems by plugging leaks and reducing unwanted airflow, energy-efficient homes help indoor air by keeping out uncontrolled airflow that can bring in moisture, pollutants and other unwanted outdoor air problems. A “tight” house with plugged leaks and controlled airflow usually results in better quality indoor air.
When making a home energy-efficient, your job is to stop the uncontrolled airflow and ventilate the air by good vacuum cleaning and strategies like cleaning up damp carpets, fixing deteriorated insulation and keeping paint cans and household cleaning products in the garage instead of the living space.
Natural ventilation is an important strategy to keeping indoor air healthy. When the weather allows it, open windows and doors. Use fans to circulate the air. Turn on the kitchen and bathroom exhaust fans to get rid of odors and humidity.
I’ve seen some studies recently that showed that many people aren’t concerned about indoor air quality and don’t even think of it as a problem. But if you’ll think about the many things we do that affect indoor air – burning candles and incense, keeping pets indoors, not changing furnace filters, and other behavior patterns – you realize that ventilation is essential.
You ought to contact your local American Lung Association chapter and get some of their information on “healthy houses.” There are many simple things you can do to keep your home’s air healthy. Combine these strategies with energy efficiency to maximize the benefits.
Q: You wrote a while ago about getting a home’s ductwork check for leaks or holes, and we hired a local contractor to do this for us. He fixed a number of problems he found and our air conditioner worked better than ever afterward. How come you don’t urge everyone to get their home’s ducts cleaned and repaired?
A: Well, I do (sort of).
I’ve been writing about the importance of clean, well-sealed ducts for the past 20 years or so, and I’m a big believe in the importance of properly performing ducts. As I’ve said many times, you can do all the things you want to make your home more energy efficient, but if the ducts are leaking, you’re going to wipe out all the savings from the other things you do.
The problem is that cleaning and repairing ducts is something to be done only by experienced professionals or you can end up with more problems than you started with. Take some of the register covers off the return ducts in your home and look inside. If you see that the ducts are really dirty or if there is light coming in through holes and tears, call a professional to come out and fix things. Holes in ductwork cause significant energy losses, and dirty ducts will bring in unwanted air pollution. You can often notice duct problems if your energy bills are suddenly going way up or if you find lots of dirt coming in through the registers. Check the walls and carpeting around air intakes for especially dirty spots.
However, poking around in ducts can cause rips and holes, and you need to be sure that you’re hiring a contractor who knows how to fix and clean these systems. I always recommend you get the ducts inspected if you suspect there might be problems, but I have to add the caution that you don’t just get them cleaned without an inspection revealing problems. And like I said, make sure you hire experienced people to do the work. This is no job for a do-it-yourselfer.
Ken Sheinkopf is a communications specialist with the American Solar Energy Society (www.ases.org). Send your energy questions to email@example.com