Expert tips for healthy indoor air: How to improve your home's air quality yourself!

Clean indoor air is essential for both health and well-being, but what's the best way to monitor its quality? We asked an expert for their top tips on improving indoor air.

Good indoor air quality is vital in Finland, as the darkness and cold keep us indoors for much of the year. Fluctuating weather conditions also pose their own challenges; we often find ourselves needing extra heat one moment and dealing with the heat with the windows wide open the next.

Indoor air quality undeniably impacts health. Poor ventilation, incorrect temperatures, and humidity imbalances can cause respiratory issues, headaches, and sleep problems. If these issues persist, they can become chronic and even lead to conditions like asthma. That’s why it’s important to monitor your indoor air and pay attention to how you feel.

“Respiratory symptoms or skin and eye irritation are often the first signs, but symptoms vary widely depending on what is affecting the air,” says Katariina Ijäs, an expert from the Allergy, Skin and Asthma Federation.

It pays to monitor indoor air quality

While indoor air issues are often noticeable through your senses, monitoring devices can help track air quality and identify problems. For instance, monitoring indoor temperature year-round is beneficial, as both excessive heat and cold are problematic. Ijäs also suggests using a hygrometer to measure humidity if you suspect there are issues with the humidity balance.

According to Ijäs, ideal indoor humidity during the heating season is 20–45%. In summer, indoor humidity typically varies with outdoor levels, ranging between 50–70%. High summer humidity doesn't usually cause problems for buildings since moisture levels are higher everywhere. However, in winter, when it's dry outside, indoor air shouldn't be too humid to prevent it from condensing on surfaces and creating a risk of moisture damage.

“You should always measure indoor humidity before buying a humidifier to avoid making matters worse, as excessive moisture is also harmful,” Ijäs explains. “Especially during the winter season when indoor air is often drier, excessive humidity can lead to moisture issues.”

Ijäs recommends choosing warm-mist humidifiers to prevent impurities from being released into the air with the steam. It's also good to opt for fragrance-free models.

“We also advise against overly noisy devices so they can be left running at night,” Ijäs says. “Ease of use is essential for air purifiers to ensure the device is maintained and filters are changed regularly.”

Generally, there's no need to worry about indoor air issues if you monitor the indoor temperature, ensure the ventilation is working and properly maintained, and the air doesn't feel stuffy.

“Your own sensory observations are the most important first step,” Ijäs reminds.

How to improve indoor air quality yourself

Good indoor air quality also depends largely on the residents: for instance, using excessive chemicals during daily cleaning or, on the other hand, neglecting cleaning altogether affects the air you breathe. However, indoor air quality is also affected by surface materials such as paints and furniture—something people often overlook.

“I recommend choosing either fragrance-free or low-emission, M1-labeled materials. This reduces the risk of unnecessary emissions from materials into the indoor air,” says Ijäs.

Regularly cleaning ventilation ducts and equipment and changing filters is vital for effective ventilation. If you air out your home frequently, it's important to consider outdoor pollutants.

“If replacement air enters through ventilation windows, pollen, street dust, and other particles like traffic emissions can enter from outside, especially in the spring. These cause symptoms for many people,” Ijäs notes.