Breathe easier at home with these pro tips.

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Q: This winter, my family and I have been spending a lot of time bundled up indoors. Is breathing all this indoor air good for us? 

A: We spend most of our lives indoors. Whether at work, school, shopping, dining or comfortably ensconced in our homes, the average American easily spends 90 percent of their time inside buildings. Just think about how much time you’ve already spent indoors today.

Unfortunately, indoor air quality is rarely as good as fresh outdoor air. But ideally it should be. We should all think more about how indoor air quality affects our health, and what we can do to improve it. Healthy indoor air should be fresh, maintain comfortable temperature and humidity levels, and be free of chemicals, mold and other contaminants.

There are many ways to improve indoor air quality that will make your living space more comfortable, save energy and money, and improve health outcomes for you and yours. Proactively limiting the introduction of pollutants into your home is the first crucial step for protecting indoor air quality, but eliminating all potential pollutants is impractical.

For this reason, mechanical ventilation is critical for improving occupant health. Additionally, it will increase the long-term durability of your home.

In Washington, state building codes have required mechanical ventilation in all homes constructed after the implementation of the 1991 Ventilation and Indoor Air Quality code (VIAQ). Many homes built before the VIAQ also had some sort of ventilation system installed. These systems may be as basic as exhaust fans installed in bathrooms and kitchens to dispel odors, moisture, particulates and other indoor pollutants where they are produced.

Some homes may also have a dedicated whole-house ventilation system that runs continuously, constantly flushing pollutants at a low flow rate. Some whole-house ventilation systems not only exhaust pollutants but also supply filtered and sometimes tempered outside air (or low-temperature air used to regulate indoor air temperature) to the living and sleeping areas of a home.

Mechanical ventilation systems don’t just guarantee better indoor air quality; they also help mitigate potential moisture-related building durability issues. Moisture generated from everyday activities can build up in the air and condense on the many surfaces within the home if not evacuated effectively. That mildew growing on the grout in our bathrooms is an obvious symptom of ineffective or nonexistent exhaust ventilation.

More concerning than a little mildew is moisture condensing, undetected, within our home’s structural cavities. While relatively uncommon, moisture that’s ineffectively managed can migrate into inaccessible wall or attic cavities, resulting in serious health problems and compromised building durability.

Keep in mind that just because your fan is making noise does not mean it is effectively eliminating moisture and potential pollutants. The duct work connecting the fan to the outdoors needs to function as intended to clean the air. Often duct work is compromised by improper construction, limiting the ability of some fans to move air and moisture to the outside of the house.

Sometimes problems arise because those of us living there simply do not understand how our actions lead to ineffective ventilation. How long should we run our bath fan after a shower? And how important is that range hood anyway? These are questions you might find yourself asking.

If you want to answer these questions and are interested in obtaining more information on residential ventilation systems, check out the video “Fresh Air for a Healthier Home,” produced by the Washington State University Energy Program. The information in the video is well vetted and presented by regional and national experts on the subject. And when it comes to indoor air quality, the more you know, the healthier you — and your home — will be.

Lucas Howard is an indoor air quality specialist at Panasonic Eco Solutions and is a member of the Master Builders Association of King and Snohomish Counties (MBAKS), and HomeWork is the group’s weekly column. If you have a home improvement, remodeling or residential homebuilding question you’d like answered by one of the MBAKS’s nearly 3,000 members, write to homework@mbaks.com.