The makeup of your indoor air changes with the seasons. To maintain healthy air quality year-round, it’s essential to understand how temperature, humidity, outdoor pollutants, ventilation patterns, and lifestyle habits shift over time, and how those shifts affect the air quality indoors.
How Spring Affects Indoor Air Quality
Spring is a wonderful time of the year as it offers pleasant weather, increased daylight, and the vibrant reawakening of nature after winter. It’s perfect for most things, but not for your indoor air quality.
For starters, this is a challenging time for household members with respiratory conditions. Many plants release pollen in spring as part of their reproductive cycle. While essential for ecosystems, it’s a major airborne irritant for people with allergies or asthma.
Additionally, spring usually brings higher humidity. The increased rainfall and warmer temperatures create a more moisture-rich environment. Elevated concentrations of water vapor in the air can promote mold and mildew growth, dust mite proliferation, and VOC off-gassing (accelerated release of volatile organic compounds from building materials, furniture, and household products). High humidity alone can degrade indoor air quality, but when combined with its cascading effects, it creates a perfect storm for respiratory discomfort.
Improving Indoor Air Quality in Spring
To improve your indoor air quality in spring, start by replacing or washing your filters. A clean, efficient filter is essential for trapping pollutants and particles that enter your home or are already circulating indoors. Once installed, continue to monitor your filters regularly to ensure they aren’t clogged or losing effectiveness, especially during peak pollen season or after heavy winds. Many homeowners inspect their filters once a month to ensure they know when it’s time for a fresh one.
Next, control your indoor humidity effectively. Consider investing in a whole-home dehumidifier to keep your humidity levels between 30% and 50%. This range helps prevent issues like mold growth, dust mite proliferation, and structural damage. It’s also ideal for your overall health and well-being.
Also consider purchasing an air purification system. Your HVAC filters will do a good job of cleaning your air, but they may not be sufficient. Residential HVAC filters typically have a MERV rating of between 5 and 13. Finer particles like VOCs, fumes, odorant particles, and some allergens may slip through.
Supplement your HVAC system’s filters with a dedicated air purifier equipped with highly rated filters. For example, systems with HEPA filters can capture pollutants as small as 0.3 microns. They can trap viruses, fumes, smoke, and ultrafine allergens. If your air purifier includes activated carbon filters, it will also absorb odors and gases, further enhancing your indoor air quality.
Summer’s Impact on Your Indoor Air Quality
After spring, summer introduces a new set of indoor air quality challenges. As temperatures rise, windows and doors are often closed to keep cool air in and hot air out. While this improves efficiency, it also reduces ventilation, allowing indoor pollutants to accumulate.
High humidity is also a major problem in summer. Soaring temperatures accelerate evaporation from water bodies and soil, increasing the amount of moisture in the air. Just as in spring, this will encourage mold growth, VOC off-gassing, musty odors, and dust mite proliferation.
The hot months can also create ideal conditions for ground-level ozone formation. Ozone is a secondary pollutant, meaning it forms through a chemical reaction rather than being emitted directly. This reaction occurs when sunlight interacts with nitrogen oxides and volatile organic compounds, which come from sources like vehicles, industrial processes, and products such as paints and solvents. The visible result of this reaction is often smog, which can affect air quality and public health.
Ozone is a problematic pollutant. It leads to coughing, difficulty breathing, increased frequency of asthma attacks, lung damage, and aggravation of lung disease.
Improving Air Quality in Summer
As with spring, a whole-home dehumidifier is excellent for controlling high humidity. 30% to 50% is the optimal level for all seasons.
A high-quality air purifier can trap accumulating contaminants. However, models that only have a HEPA filter do not neutralize gases like ozone. For summer, you should have a purifier that includes activated carbon filters.
Inspect your insulation and seal all leaks and cracks. Not only will this keep cool air inside, but it will also keep moisture and pollutants out.
Fall and Indoor Air Quality
Fall is known for stale air and allergens. As temperatures drop, homes are sealed up, trapping lingering summer pollutants and encouraging the growth of harmful microorganisms. Plus, the various holiday celebrations, like Halloween and Thanksgiving, make the situation even worse. Some candles emit irritating chemicals when burned, and natural decorations like pumpkins release toxins as they decay.
Allergies may also flare up due to fall-blooming plants, such as ragweed. Pollen can sneak in through open windows during the day or through gaps around doors and poorly sealed frames, settling into carpets, upholstery, and fabrics.
Improving IAQ in Fall
Fall and winter holidays usually mean more activity in your home, such as cooking large meals and hosting guests. Consider upgrading exhaust fans in kitchens, bathrooms, and laundry rooms to remove moisture, odors, and airborne contaminants. On mild days, open windows briefly to refresh stale indoor air but avoid doing so during high pollen counts or windy conditions.
Be mindful of seasonal décor. Choose artificial decorations over organic ones if allergies are a concern, and opt for beeswax or soy-based candles with cotton wicks to avoid VOCs and chemical irritants.
Additionally, extra cleaning helps. Vacuum regularly with a HEPA-equipped model and dust with damp cloths to reduce allergen buildup in your home.
Indoor Air Pollution in Winter
Winter is known for dry air and poor ventilation. Humidity drops significantly during colder months because cold air simply can’t hold much water vapor. Your sinuses may feel dry and irritated, as cold winter air will strip moisture from your nose, throat, and lungs.
In addition to dryness, winter brings increased exposure to combustion pollutants. Gas furnaces, fireplaces, wood stoves, and space heaters can release carbon monoxide, nitrogen dioxide, and fine particulates into your indoor environment. These byproducts can cause headaches, dizziness, respiratory irritation, or other health issues if ventilation is inadequate.
Solutions Catered to Winter
A whole-home humidifier is important to maintain good indoor air quality in winter. It adds moisture to the dry air, improving respiratory comfort, reducing static electricity, and protecting furniture, paint, and other structural materials from cracking or warping.
Follow that up with a focus on safety. Your heating system, fireplaces, and gas appliances should operate efficiently and have proper venting. Install carbon monoxide detectors near high-risk zones and sleeping areas, and test them monthly.
Make sure your air purifier is well-maintained. You probably keep your home tightly sealed up in winter to save on heating costs.
Contact Your Local HVAC Experts
At My Guy Heating and Air, LLC, we proudly serve homeowners in northern Colorado and have over a decade of experience helping our customers improve their comfort and safety. We can test your air quality and provide tailored solutions for your home. Be sure to ask us about our maintenance plans!
Contact My Guy Heating and Air, LLC in Longmont to schedule an appointment with one of our experienced technicians.
