How Winter Affects the Air Quality in Your Home

Americans spend about 90% of their time indoors, with much of that time spent at home. During winter, this percentage increases even further, making indoor air quality a critical concern. Poor air quality can contribute to both immediate and long-term health effects. Here’s a closer look at how winter conditions can influence the air quality in your home.

Higher Pollution Concentration Levels

Pollution levels in the home often increase during winter due to several factors. For one, outdoor pollution significantly impacts the quality of indoor air, and pollution levels tend to be higher in colder months. Many homes and businesses run fuel-based heating systems, and vehicle emissions increase in low temperatures. Additionally, cold air is denser, slowing down its movement and allowing pollutants to accumulate. Temperature inversions in winter, where warmer air traps pollutants near the ground to prevent them from dispersing, can further increase pollution levels.

Another factor is the airtight structure of many homes. Modern homes are built to be highly energy-efficient, which requires tightly sealed construction. While this reduces energy costs, it also limits natural ventilation, and this causes pollutants to accumulate indoors. Many homes rely solely on heating systems for ventilation, which may not be sufficient. To improve ventilation, consider adding a mechanical ventilation system like a whole-house fan. For winter use, heat and energy recovery ventilators are excellent options, as they provide fresh air without compromising indoor warmth.

More Time and Activities Indoors

Behavioral factors also impact indoor air quality in winter. People tend to stay indoors longer, and households may have more members at home. This leads to increased indoor activities that can inadvertently introduce pollutants. The limited ventilation in winter compounds this effect, allowing indoor pollutants to linger. Sources of indoor pollution can include household cleaners that release airborne chemicals and volatile organic compounds (VOCs) that off-gas from furnishings, electronics, and other belongings. Cooking more frequently in winter can also introduce particulates and gases into the air, further reducing air quality.

Lower Relative Humidity

Relative humidity (RH) is a crucial factor in indoor air quality. RH refers to the amount of moisture in the air relative to its temperature. Cold air naturally holds less moisture, which is why it tends to be drier during winter. The Environmental Protection Agency recommends maintaining indoor RH above 30%, while many health experts advise a minimum target of 40% for optimal comfort and health.

Low RH can lead to several discomforts, including dry skin, throat irritation, and increased vulnerability to respiratory issues. Achieving ideal humidity levels in winter can be challenging without a humidification system. Portable humidifiers are an option for localized humidity control, but they require frequent cleaning and refilling. If neglected, a dirty humidifier can actually harm indoor air quality. A more efficient solution is a whole-home humidifier, which requires only annual maintenance and draws water automatically. Whole-home humidifiers also allow you to set a precise RH level for consistent indoor comfort.

Heating Your Home

Heating systems can contribute to indoor air pollution by adding particulate matter and gases to the air. To minimize this, it is important to schedule a heating tune-up before winter begins, as annual tune-ups ensure systems operate safely and efficiently. Also, ensure your carbon monoxide detectors are functioning properly and replace batteries or units as needed. Be cautious with combustion-based space heaters and wood-burning stoves or fireplaces, as they can emit harmful gases and particles.

Heating also contributes to the problem of low relative humidity by rapidly warming cold, dry air, which can then absorb moisture from the indoor environment. This process can draw moisture from surfaces like wood floors and even from the respiratory system, and this can potentially cause irritation and discomfort. Low humidity due to heating can also affect wood furnishings and cause them to crack or warp over time. Proper heating system maintenance and duct cleaning will reduce the amount of pollution your furnace adds to the indoor air.

Respiratory Irritation and Illness

To combat respiratory irritation from dry indoor air, many specialists recommend a whole-home humidifier. Dry air can irritate the respiratory tract, leading to inflammation, fatigue, and general discomfort. This irritation may also increase susceptibility to illnesses such as colds and the flu. For added protection, consider installing an ultraviolet (UV) light in your ducts, which can neutralize over 99% of airborne bacteria and viruses to reduce the risk of illness. UV lights are an especially helpful addition for families with young children or elderly members who may be more vulnerable to respiratory issues.

Indoor Air Quality Solutions in Ohio

KW Lang Mechanical is a trusted HVAC provider serving Solon, Ohio, and the surrounding communities for decades. Our team offers installation and maintenance of air purification systems, UV lights, humidifiers, dehumidifiers, whole-house fans, and other air quality solutions. We also work with furnaces, heat pumps, air conditioners, and ductless mini-split systems, specializing in green HVAC options like geothermal, VRF, and VRD systems.

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