An air cycle house where the air flows invisible places

”Creating healthy housing with positive thinking ”published in 1994

Japanese page

Let’s think about how to eliminate the cold part of the building from the architectural method.

The invisible part is the decisive theme of health.
From a health point of view, the biggest advantage of the conventional frame construction method is that there are places that cannot be seen.
It is an underfloor space, a space on the first and second floors, a hut space, and an inner wall cavity.
It is to connect with one another, and that is the path through which air flows.

From now on, let’s call this connected space a “body space”. The PAC house completely created this “body space”.

In the PAC house, the underfloor ventilation port and the ridge ventilation port are opened in the summer, and a series of vertical ventilation such as nighttime cold air is generated in the “body space” which is useful for creating a healthy house in the summer.

This time, the theme is winter, so close the ventilation port mentioned above and switch to winter mode.
With this, the outside air is cut off, but the air flow in the body space is different from that in summer.
The air in the inner wall cavity of a room with a relatively high temperature such as a living room is warmed from the indoor side and the air rises.

On the other hand, the air in the inner wall cavity, such as a closet, which has a relatively low temperature, is cold and therefore descends.

These two air flows act as a driving force to create air circulation in the “body space” .

It can be said that the so-called air cycle house was created at this stage.

In an air cycle house, the entire building is insulated outside the structure such as columns and beams, and in winter the upper and lower ventilation ports are closed, making the building highly airtight.

But inside the building, air is flowing in the “body space”

The story is a little off, but do you know the following words?
“Let the flowing air touch the wood.”
As long ago, in Japan, people who handle trees have said that in order to prevent the wood from rotting, it means that they should not be placed in a stagnant place in the air.

You can understand it even if you think about it in the laundry. If there is even a little wind, the dry condition will be much different than when there is no wind.
And fortunately, most of the important timber that makes up a building, such as its foundations, columns, and beams, is in this “body space” where constantly air flowing.

Let’s think about dryness a little more.
So what happens to the dry state if the temperature of this flowing air is high?

Naturally it will improve.
It’s the same as drying laundry in the daytime rather than at night.
Similarly, the warmer the air flowing through this “body space” will make it even drier, making the building more durable and protecting the home from the harmful effects of various moistures

At the same time, you noticed that it also plays a role in removing the cold places in the building mentioned in the previous theme, and contributes to the health of the residents.

Air cycle homes are insulated outside the building structure and not around the room, so the heat generated inside the room is transferred from the ceiling and interior walls to warm the air in this “body space” .

What kind of heat is generated in the room?
There are two main types. Life heat and solar heat.
This life heat is great surprisingly.
It also comes from lighting fixtures, refrigerators, televisions, cooking, baths, heating and the human body. There is no way not to take advantage of this heat.

Unfortunately, ordinary houses are insulated around the room, so it can not happen.

In this sense, air cycle homes can be called recycled homes. This is the reason why it is highly effective even in places with poor sunshine conditions such as snowy countries.

Now let’s look at the heat of the sun.

The sunlight coming in through the windows warms the room. The heat is transmitted from the ceiling and inner wall to the “body space”, and then travels to every corner of the building along with the air flowing.

It is the conventional frame construction method that can construct this “body space” .
It has changed a lot from the old clay-walled house, but it may be said that the goodness of growing up in Japan remains in a different sense.

However, unfortunately, this “body space” is not utilized even in the conventional frame construction method.

As we have seen, the “body space” plays an important role in most elements of a healthy home, such as warmth, coolness, elimination of temperature differences, humidity control, and drying of wood.

The goodness of wooden houses is often touted, but I would like you to reaffirm this hidden and invisible important part.


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