A house where penguins and cats live together

We want a warm house.

This has been the wish of the Japanese people for a long time. Heating did not work at all in the traditional Japanese house. Even with heating, the rooms never warmed up.

So when did it become possible to warm a room with a stove in it? It wasn’t that long ago.

This was the time when windows were replaced with aluminum sashes, walls with mortar or siding, and foundations were built entirely with concrete.

Around this time, oil heaters started to come into the rooms more and more. Many people must have been thrilled with the warmth of the room.

With the introduction of aluminum sashes, mortar walls, concrete foundations, and insulation in the walls, the gaps in the building became much smaller than they had been before, and the rooms were much better heated. Many people were very happy about this.

Carelessly, however, most people did not realize at the time that this would also cause the building to become hotter in the summer, and the damage caused by the humidity would eventually become more rampant.

Today’s highly insulated and airtight houses are an extension of this.

With the heating on, the house became a place where penguins and cats could live together. Cats in the heated rooms and penguins in the unheated rooms and hallways.

For example, it is 25 degrees in the heated room and 4 degrees in the hallway. A difference of more than 20 degrees Celsius has become a common occurrence. At the time, we were simply happy to have warmer rooms.

Even today, many houses are being built where penguins and cats can live together. I would like to emphasize again that the place where penguins can live is “the cold places in the building.

The unhealthy life in winter lies in this temperature difference.

“Cold places in the building” This is the root of all evil.

I apologize to Penguin, but for many years I have been building healthy houses that eliminate the “cold places in the building”.


From now on,
Let’s explore the root cause of the evil of “cold places in the building”.

In winter, all the unhealthiness and harm in the building occurs on the cold places in the building. We thought that if we could eliminate the cold places in the building, it would naturally lead to a healthy house.

Moisture damage.

We all know that moisture-related problems, such as mold growth and mites that can cause atopic dermatitis, occur in cold areas of a building, such as the north side of a building, where there is no sunlight and poor ventilation.

The building will rot.

The structural materials of the foundation, pillars, and roof rot away without knowing it.
There was an example in the newspaper of a building rotting due to condensation caused by a failure to install insulation.
Is it the foundation of the south side? Is it the north side? 
In most cases, it will be the cold north side where condensation easily occurs.

There’s a wind in the gaps.

A door between a warm, heated room and a cold hallway. The moment this door is opened, a cold breeze flows from the hallway into the room.
In the past, a wind in the gaps were caused by cold outside wind blowing in through gaps in fittings and walls, but nowadays, a wind in the gaps are caused by air convection due to temperature differences between spaces.

It could trigger a stroke.

Even today, vascular diseases such as stroke and myocardial infarction still pose a great threat to the health of the Japanese people.
In the past, too much salt was a major cause, but nowadays, the westernization of the diet, with a focus on meat and oily foods, is adding to the problem.
If you have high cholesterol or triglycerides and high blood pressure, you should be careful.

Many times, an half asleep old person with high blood pressure walks from a warm, heated room to the bathroom through a cold corridor, which leads to misfortune.
I often wonder if the same thing would happen if the latrine was outside, like in the houses of long ago.

It is very inconvenient to have a latrine outside. It was a hassle to get there, and in winter it was very cold.
However, it was also a good thing.
When I had to urinate, my mind started to clear, wondering if I could hold out until morning, or if it would be cold outside.
And by the time I decide to go, I’m ready to go, it’s cold outside, I’ll be careful, and my body is ready for it.

Therefore, you are less likely to suffer from a stroke due to the sudden temperature difference.
I think the goodness of the outside latrine was that you couldn’t casually go there with sleepy eyes.

Perhaps the tragedy of our time is that now that the toilet is inside the house, we can go to the toilet in the middle of the night without worrying about it.

So many rooms unused, what a waste!

This is also related to the floor plan.
Even if you build a big house with lots of rooms, the number of rooms that are actually used is probably very small.

The family often gathers in the living room or in the tea room connected to the kitchen.
The room on the north side of the hallway has become an unused room.

In the past, the number of families was large, but nowadays, the number of families has drastically decreased, it is only natural that the cold rooms on the north side of the building, which do not get enough sunlight or ventilation, are not used.

These are the typical damages that occur in “cold places in buildings”.

The key word for a healthy house is to eliminate cold places in the building.

The term “in the building” covers not only interior spaces, but also all spaces other than living spaces, such as underfloor spaces and interior wall cavities.

And “to eliminate cold spaces”. This does not mean to warm them up. It means to make the temperature in the middle, neither cold nor hot.

Yoshiaki Tanaka
This is a sentence from the book “House made by feeling the life of a married couple”.


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