Around 80% Answered They 'Didn't Know' About 'Homes with Clean Air Without 24-Hour Mechanical Ventilation'. What is the Awareness of Indoor Air Environment in Homes?
This survey explores awareness regarding indoor air quality and its impact on health among homeowners in Japan, revealing a significant lack of knowledge about homes that maintain clean air without continuous mechanical ventilation.
📋 Article Processing Timeline
- 📰 Published: April 7, 2026 at 20:00
- 🔍 Collected: April 7, 2026 at 11:31
- 🤖 AI Analyzed: April 18, 2026 at 10:12 (262h 41m after Collected)
■ Survey on Awareness of Home Air and Indoor Environment
Have you ever suddenly noticed the indoor air in your daily life?
The lingering smell after cooking, the stuffy humidity during the rainy season, the frustration of not being able to open windows during pollen season. The accumulation of these small discomforts is actually becoming a major point in choosing a home.
Therefore, this time, in collaboration with Trust Home Co., Ltd., we conducted a survey on "Awareness of Home Air and Indoor Environment and its Impact on Health" targeting 350 men and women nationwide who answered "live in a detached house they own" in a preliminary survey.
※ When citing the contents of this press release, please do the following:
・State that the source is "A survey by NEXER Co., Ltd. and Trust Home Co., Ltd."
・Set a link to Trust Home Co., Ltd. (https://t-trust.co.jp/)
"Survey on Awareness of Home Air and Indoor Environment and its Impact on Health" Survey Overview
Survey method: Internet questionnaire
Survey period: March 19, 2026 - March 26, 2026
Respondents: Men and women nationwide who answered "live in a detached house they own" in a preliminary survey
Valid responses: 350 samples
Questions:
Question 1: Have you ever been concerned about the indoor air quality of your home (cleanliness, ventilation, odor, etc.)?
Question 2: When did you particularly notice it?
Question 3: Did you know that there are "homes with clean air without 24-hour mechanical ventilation"?
Question 4: Do you want to prioritize "clean air and indoor environment" when choosing or building a house?
Question 5: Please tell us the reason.
Question 6: How important do you think the "home air environment" is for protecting your family's health?
Question 7: Please tell us the reason.
※ In principle, fractions of 0.01 and above are rounded up, so the total may not be 100%.
■ 45.4% Answered They Had Been "Concerned About Indoor Air Quality"
First, we asked if they had ever been concerned about the indoor air quality of their home (cleanliness, ventilation, odor, etc.).
As a result, 11.1% answered "often" and 34.3% answered "sometimes," for a total of 45.4% of people who have experienced being concerned about indoor air quality.
On the other hand, 35.7% answered "rarely" and 18.9% answered "never."
Although not many people are strongly aware of it on a daily basis, it is clear that about half of them have been concerned. It seems that indoor air, which is usually difficult to be aware of, can sometimes become a concern due to small triggers. This can be said to be an unignorable result when considering the comfort of a home.
We asked when they particularly noticed it, and here are some of the answers.
When did you particularly notice it?
・Because I have dogs and cats, I am concerned about pet odor. (20s, Male)
・When I couldn't open the window all day, like during yellow dust. (30s, Female)
・During infectious disease season. (30s, Male)
・Whether pollen has entered the room during pollen season. (40s, Female)
・After cooking yakiniku or garlic dishes. (40s, Female)
・Sweaty smell when I was at work all day. (40s, Male)
As situations where air quality is a concern, pet odors and cooking odors were prominent. Also, many people are aware of stuffy air when it's difficult to open windows, such as during pollen or yellow dust seasons, or when infectious diseases are spreading.
Furthermore, it can be inferred that the longer one stays indoors, such as for remote work, the easier it is to notice changes in the air.
■ 80.3% Answered They "Didn't Know" About "Homes with Clean Air Without 24-Hour Mechanical Ventilation"
Next, we asked if they knew about "homes with clean air without 24-hour mechanical ventilation."
80.3% answered "didn't know," which was an overwhelming majority.
"Heard the name before" was 12.9%, and "knew about it" was only 6.9%.
It is clear that the mechanism of houses that can maintain a good air environment without relying on mechanical ventilation is not yet widely known. While attention tends to be focused on insulation and earthquake resistance when it comes to house performance, information regarding indoor air environments does not seem to have reached many people yet.
■ 73.4% Answered They "Want to Prioritize" Clean Air and Indoor Environment When Choosing or Building a House
Next, we asked if they wanted to prioritize "clean air and indoor environment" when choosing or building a house.
23.1% answered "strongly want to prioritize" and 50.3% answered "somewhat want to prioritize," for a total of 73.4% who want to prioritize clean air and indoor environment. 18.6% answered "don't really prioritize" and 8.0% answered "don't prioritize at all."
In the previous question, over 80% of people did not know about homes with clean air without 24-hour mechanical ventilation. However, on the other hand, over 70% of people want to prioritize the air environment when choosing a home.
It can be said that many people desire to live comfortably in clean air, even if they don't know the specific mechanisms.
We asked why they want to prioritize "clean air and indoor environment," and here are some of the answers.
Reasons for wanting to prioritize "clean air and indoor environment"
・Because the indoor environment of a place I might live in the future is sufficiently important for my future life. (10s, Male)
・To reduce the effects of pollen, house dust, and mold. (30s, Male)
・Because I have asthma, and when the air is bad, my throat hurts and I cough. (30s, Male)
・Because I think I can stay calm if I spend time in a clean environment. (40s, Female)
・Because it's a place where I spend time every day, I want to spend it in good air. (40s, Female)
・Because I want to live healthily in a clean air living environment, including room temperature. (50s, Male)
As reasons for prioritizing, consideration for health aspects was the most common. While there were calls for improving the air environment due to specific symptoms such as hay fever, allergies, and asthma, there was also a high awareness of the quality of life, saying, "I want to be comfortable because it's a place I spend every day."
■ 82.3% Answered That the Home Air Environment is "Important" for Protecting Family Health
Finally, we asked how important they thought the "home air environment" was for protecting family health.
34.6% answered "very important" and 47.7% answered "somewhat important," for a total of 82.3% who considered it "important." 12.6% answered "not very important" and 5.1% answered "not important at all."
Many people seem to perceive the home air environment as deeply related to family health. It can be inferred that many people feel that the quality of air affects their physical condition and ease of living precisely because it is a place where they spend a long time every day.
We asked why they thought the "home air environment" was important, and here are some of the answers.
Reasons why the "home air environment" is important
・Although I don't know how much it affects health, I feel safe when the air is in a good state. (20s, Male)
・So I don't have to take time off work due to my child's poor health. (30s, Male)
・Because I have a child with house dust and dust mite allergies. (40s, Female)
・I think ventilation is important for things that harm health, such as viruses, dust mites, and pollen. (40s, Male)
・Because the air in the place where I live every day directly affects my family's health. (50s, Male)
・Because it's the space where I spend the longest time. (50s, Male)
Among the reasons for considering it important, many people cited specific health risks such as allergies and respiratory effects.
Also, some mentioned that their child's poor health affects their work and overall life, indicating that the home air environment is not just a matter of comfort, but is considered the foundation that supports family life.
■ Summary
In this survey, about half of the people living in detached houses have experienced being concerned about indoor air quality, and more than 70% answered that they want to prioritize the air environment when choosing a house. Furthermore, over 80% feel that the air environment is important for protecting family health.
On the other hand, the existence of homes with clean air without 24-hour mechanical ventilation was unknown to about 80% of people. This highlights the current situation where, despite high interest in the air environment, information about available options has not yet sufficiently reached many people.
Since the air in a home is invisible, why not also consider the structure and ventilation system when considering a house?
＜For use in articles, etc.＞
・State that the source is "A survey by NEXER Co., Ltd. and Trust Home Co., Ltd."
・Set a link to Trust Home Co., Ltd. (https://t-trust.co.jp/)
【About Trust Home Co., Ltd.】
Location: 〒300-0726 1530-1 Nishishiro, Inashiki City, Ibaraki Prefecture
Representative Director: Yasuyoshi Shinozuka
TEL: 0299-80-5561
Business activities:
General wooden construction design and construction, general steel frame construction design and construction, exterior construction work, renovation work
【About NEXER Co., Ltd.】
Headquarters: 〒170-0013 Rise Arena Building 11F, 4-5-2 Higashi-Ikebukuro, Toshima-ku, Tokyo
Representative Director: Yuya Miyata
Business activities: Internet research, SEO, WEB branding, review content, real shop support, WEB site production