Poisonous gas in underfloor

Anti-termite measures and termite prevention at the expense of family health.

“Underfloor poisonous gas”

In 1994, I learned the horror of termite control agents with this word.

At that time, I was very shocked when I encountered the term “poisonous gas under the floor” in the book “Pesticides and Environmental Destruction Episode 56” by Professor Tatsuo Kato, a professor at the Center for Environmental Science, Yokohama National University.

Immediately, I visited Dr. Kato to reaffirm the horror and have him conduct a substantive survey at the PAC house.

At that time, it was called the PAC group and was being promoted by a membership system of construction shops.

With the cooperation of member companies, we conducted air analysis of the underfloor space and each room on the first and second floors for PAC houses immediately after new construction and PAC houses that have passed one summer.

At the time of 1994, unlike now, there were no healthy building materials, so at the construction site, tears appeared in the eyes, the nose was tingling, and the throat hurts. Even after moving in, the degree was only lightened, and there was similar discomfort.

Among them, in the case of PAC houses, after spending one summer, such discomfort and odors disappeared indoors.

This is because the air flow in the summer skeleton space of the PAC house volatilizes harmful chemical substances inside the building and throws them out.

This is because the air flow in the summer skeleton space of the PAC house volatilized harmful chemical substances inside the building and throws them out.

However, more than 20 other chemicals that were previously detected in the survey of the materials used in the building were brilliantly removed from the building and were not detected by mechanical analysis, nevertheless only the harmful chemical components of the termite control agent remained and were detected at high levels in the indoor air.

This was horrifying, and after serious discussions with the member companies at the time, we immediately abolished the anti-termite treatment with chemicals.

Originally, PAC houses were well-ventilated under the floor, inside walls, and behind the ceiling throughout the year, and the moisture content of structural materials such as foundations for a long period of time was measured by university institutions,.
And it was confirmed that they were extremely dry.

Therefore, we were able to stop the termite control treatment with chemicals that cause health problems with peace of mind.

At that time, the Government Housing Loan Corporation required anti-termite treatment with chemicals, but in discussions with the owner, we did not do anti-termite treatment that is harmful to our health.

A few years later, due to the actions we included, the mandatory termite treatment with chemicals was no longer obligatory, and the termite countermeasures by architectural methods, as was done in PAC, were finally approved.

Since 1994, PAC housing has not been treated with chemicals to prevent termites, but there have been no reports of serious termite damage even during the membership system (the PAC group was dissolved in 1997),not even now.

However, looking at the entire housing industry, termite control by chemicals is still common, and few by architectural methods.

As long as treating the structural material and ground of the building with pesticides, the insensitivity that they call it a healthy house is unforgivable.

Recently, as a new termite damage problem, the foreign origin Incisitermes minor, which prefers dry materials, has been rapidly highlighted.

Japanese termites prefer moisture and need water, but the appearance of the exact opposite termites is surprising.

It’s interesting that it works well for Japanese termites, cockroaches, and Incisitermes minor and however most importantly, the measures that do not cause any health damage for humans and pets such as dogs and cats, have appeared.

It is a measure with boric acid.

It’s getting longer, so I’d like to inform you about the items again.


  1. https://ac-renove.com/sos/sos-4/また、北側…
  2. 同じ家の中なのに、明るい部屋と暗い部屋がある。また暑いくらいの部屋と同時に寒い部屋…
  3. 自然素材のリフォームで安心して過ごせる毎日をhttps://ac-renove.…
  4. 新しい家に住んだら広くなったせいか、あまり家族が顔をあわせなくなった。子供が学校から帰ってくると自…
  5. 木造アパートのリノベーション事例です。キッチンやユニットバスの交換はもちろん、基礎や構造の耐震…