Air Quality At-Home: The Surprising Impact of Winter Weather
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Last year, we published Tips for Maintaining Healthy Air Quality During Winter, a practical guide to keeping indoor air clean when the temperature drops. This follow-up, written by Jennifer Dawson, a semi-retired environmental health technician who still keeps up with the latest research and how the industry is moving, takes a deeper look at why winter weather has such a strong grip on the air inside your home, from the pollutants that build up to the house-wide solutions that can help year-round.
The great indoors isn't always so great
While your house may feel clean enough, the great indoors can contain pollutant levels that "frequently can exceed those found outdoors," the Environmental Protection Agency (EPA) points out. While this can be a culmination of a variety of different sources (cleaning products, mold, etc.), it's crucial to understand how indoor air pollution can worsen in certain seasons, especially considering that many Americans spend much of their time indoors. While wildfires can have a more obvious impact on the air we breathe, how indoor air changes during the winter months is often overlooked. From the risks associated with the colder months to the breakdown of what's in the air, there are smart solutions that can help better at-home air quality.
Winter weather events bring extra concerns
Winter weather requires that homeowners be vigilant, as the season can bring forth problems that many might not realize. For example, in a page titled "Winter Weather and Indoor Air Quality," the EPA notes that snow (as well as ice) can create an accumulation of indoor pollutants when it comes to outdoor vents, making it necessary to stay on top of cleaning throughout the winter (think fireplace, dryer, etc.). Often a result of winter storms, power outages are another concern, the EPA further notes, which can lead to alternative sources for heating that require immense care and attention regarding use.
The risks of carbon monoxide exposure and poisoning also increase during the winter season. For example, a power outage can result in many turning to a portable generator, an appliance that must be used correctly and with the utmost care in order to avoid carbon monoxide poisoning. For example, the EPA stresses that fuel-powered portable generators should never be used indoors, or in any space that is enclosed (including the garage). Understanding the importance of using any appliance correctly and how to do so can help avoid such issues, though it's still equally as important to maintain carbon monoxide detectors throughout the home.
The air in your home: a breakdown
While many may not associate indoor air quality with winter weather, they are nevertheless linked in distinctive ways. Volatile Organic Compounds (VOCs), for instance, can become elevated during wintertime. According to a post from the American Lung Association's blog Each Breath, this can be due to a variety of factors, such as lessened ventilation, using scented candles, etc., which happen to be associated with the winter season. While VOCs can cause symptoms such as respiratory irritation, the post also notes that some are even known to cause cancer.
Additional factors that contribute to poor indoor air quality can often go unnoticed simply due to their normalcy in some homes. Routines such as cleaning, for instance, often involve products that can be hard on indoor air (especially with a lack of ventilation). One 2025 SciTech Daily article by Stanford University highlights a study (led by the University), in which gas and propane stoves were discovered to "release significant amounts of nitrogen dioxide." The article goes on to note that this is a pollutant known to be linked to asthma, as well as lung cancer among other health conditions. On the other hand, those that are avid users of wood-burning stoves or fireplaces can also face poor air quality concerns. An Earth.org article by Colin Rhodes points out the link, stating that wood smoke "is a significant contributor of the toxic air pollutants particulate matter, benzene, formaldehyde, acrolein and hydrocarbon."
Cold weather can also contribute to poor ventilation throughout the home, as many don't think to open the window for fresh air. This can not only keep harmful pollutants inside, but can contribute to further issues such as moisture and mold. Busted pipes are another unfortunate tragedy of winter weather, which can also contribute to unwanted moisture and even mold in the home. Once unintentionally invited, mold can give rise to several health effects (and physical house damage). Most prominently, mold can trigger respiratory irritation though it can also contribute to asthma attacks, resulting in a nightmare scenario for any homeowner.
Discovering house-wide solutions
The realization of how much winter weather has an impact on indoor air quality can be a harrowing thought, though there are several ways to improve the situation. Adequate ventilation, for example, is a necessity beyond summertime, and will help prevent excess moisture in the home. According to an American Lung Association (ALA) blog post by Jill Heins-Nesvold, MS, Staying Safe from Indoor Air Pollution This Winter, it's okay (and even encouraged) to crack a door or window in the winter in order to freshen the air inside. It's recommended to do so for ten minutes a day, which can work to "dilute" indoor pollution, the post states. However, it's further noted that this advice may not be suitable for those who live near sources of outdoor air pollution, in which case an indoor air cleaner can be a worthy avenue to explore. Other small (yet influential) actions, such as curating a cleaning routine that involves natural and eco-friendly products can help lower harmful VOCs. In addition to air purifiers and other cleaning systems, air quality monitoring systems can help greatly, especially when the goal is to keep a close eye on indoor air quality year round.
House-wide solutions are ideal for those that wish to better their indoor air quality all year. Insulating outdoor water pipes can be a great preventative measure to help avoid busted pipes, while the installation of a ductless A/C unit can positively contribute in other ways. Ductless systems function to properly cool the home as well as provide temperature control. These systems are well-regarded for their energy efficient nature, and can be more convenient for homeowners that don't want to invest in the full-on ductwork associated with traditional systems. Zoned cooling capabilities are another advantage of ductless systems, temperatures can be adjusted from room to room for heightened efficiency throughout the home. It's important to note that ductless systems can also apply to heating solutions, which can be great for the winter months when the goal is to apply consistent and efficient heating and cooling throughout the home year-long.
Indoor air quality is immensely important, especially when considering how much of our time is spent inside. While many may not consider weather to be synonymous with indoor air quality, the winter months can contribute to less than stellar air quality in the home. Through simple solutions, homeowners can make several positive changes to breathe easier year round.
For more practical tips on keeping your air clean when the temperature drops, see Tips for Maintaining Healthy Air Quality During Winter.
Monitor your indoor air with a PurpleAir sensor or browse air quality monitors for your home.