A "breathing" frame house

[Summer]

In winter, the moisture from the outside is very small, as for example in our region, with the average monthly temperatures at - 20, and in general it is very small (and no mystique about the properties of wooden houses can’t abolish the laws of thermodynamics (yet?) - in winter the wood dries.
And the humidity is inside, with a proper ventilation, can be maintained only by a constant vaporization and the specific numbers will depend on the intensity of this process - a kitchen, a shower, a laundry, a moisturizer - IMHO.

[constructor]

I also tried to find the answer to this question, but so far, from a company representative RUNATEL (Dnepropetrovsk), which unraveled the subject, the answer was as follows:
to accelerate the action of lignin (a clumping of mass and thus to reduce the possibility of subsidence) and the increasing density insulation. And by the way, the glue is added very seldom, only when the thickness of insulation is more than 100 mm and a glue on the basis of PVA, basically the effect is given by the water if we are spaeking about figures then 100g (a concentrated PVA) for 1 cube of water.

[Summer]

In winter, the wood gets wet. The thinner wall, so it is much wet.
My house has an excellent model.
A water pipe.
It has drops of condensation. The moisture is taken from the dry air. I wrapped the tube by the paper rope and soaked the paper by the cement.
Now, the vapor is not easy to reach a dew point. And reaching the dew point, the moisture is sent back, and the moisture in the dry air is now much easier to leave the tube. It is not as cold as before. The thicker wall, the warmer it is. And so it gives the moisture more intense.

[constructor]

As I understood in the wall from the ecowool a major obstacle to the diffusion of CO2 and O2 will be a windscreen, which by definition must be less air penetrable. On the other hand, because we need to get 50 l/hour of CO2 per person, and probably, about the same O2.
The availability of spare volume, which can be "cut off" the peak arrival of CO2 from a working person, a presence, whether we like it or not, the ventilation, at least in a bathroom and a kitchen and the presence of a heat consuming tainted air, and the impermanence of our stay in the house will reduce the need for diffusion.
So, I think that the diffusion of CO2 per person 20 l/hour is enough.
And what a windscreen must be to ensure that this diffusion took place, I can not figure out yet.
The issue also rests on the fact what we are profitable, a membrane with a low air permeability and a diffusion. While there may be some Tyvek, just, will miss the right amount of a carbon dioxide?

[expert]

I looked a design. I understand that, in fact, this window, is "curtained" by a mineral wool with more complicated than the straight route for air?. It was still easier than a car muffler.
There are few more questions on such lattices:
- How to fight the "dusting" of mineral wool (or is it not dusty?)
- Does a mineral wool hided?. (And a question to you, as a connoisseur, a mineral wool is always used in the three-layer structures?).
- The index of insulation, it seems, is equal to the performance of insulating layer ... "Not so hot," Or I will not go look?.
No doubt, the firm Halton has the answers to these questions.
As to the use of lattices, exactly they can be used, IMHO, for the ventilation of closed non-residential premises (pantries, closets). In accommodation, under the door there is usually a small gap through which the pressure is aligned in adjacent areas... Or I do not understand something?.

[bill]

A diffusion is the same wind, but the wind is not for all air gases, but one gas CO2, for example. The reason is the difference between the partial pressures. And as the membrane will delay a breeze and will miss the other one.

[baltazar]

With regard to my phrase about "the tree sucks the moisture from the outside," probably, nobody understood me.
I have had in mind:
Imagine a standard wood wall of 150 mm.
Outside is -10, 80% RH (typical values for January in Moscow).
Inside is + 20, a humidity is 40%.
According to the schedule (see an attachment), it turns out that the equilibrium moisture content of wood mass for these conditions goes up:
for the outer part of the wall: 20%
for the inner part is 8%.
So, the same stump has 200 g water per 1 kg, while the other has only 80.
Will be under these conditions a moisture transfer inside the piece of wood (through the capillaries)?
If so, what will be that direction?.
In general, I am not yet figured out (yesterday I thought it would be the transfer, now I lean to the fact it will not). Therefore, I requested the data on the actual moisture content in the wooden home.

[buldozer]

In general, for my questions, I will answer myself, because my thoughts cleared up.
A moisture transfer in any material is always directed toward reducing a partial pressure.
That is, in the case that I cited, the moisture from the inner wall (where 80g/kg) will move to the outside (where 200g/kg).
In general, the stupidity, I suggested about "sucking the moisture." I confess.
From this fact it follows that there is no capillary transport in the opposite direction to the gradient of partial pressures.
Otherwise, it would be contrary to the laws of conservation of energy and thermodynamics.
In other words, no "return" of condensed moisture in the wall back into the room can not be, as you did not want to.
80g - 8% - with an internal air, it does not replenished, just inside the T supported.
It's kind of like on the condition I was so conceived.

[constructor]

80g - 8% - with an internal air, it does not replenished, just inside the T supported.
It's kind of like on the condition I was so conceived.
The water is another gin. This is not a gas. The force of gravity takes action on it.
In addition to it, the capillary forces of molecular cohesion act.
And here the gas laws?
This is the same diffusion!
Only the diffusion of water!
This is what we will create somewhere a higher humidity and the water will flow back to this place?

[bill]

Excuse me, why?. A partial pressure refers to the gaseous water. A liquid water evaporates under the humidity around, because the "partial pressure" of water molecules in the water is always higher than in the atmosphere. And if a piece of wood on one side 20% humidity, and with another 8%, then it will be dry on both sides, but a second faster.
A capillary water is taken from the air.
Drying, they must be replenished. A circulation you know!. The state of equilibrium.
As such forces as long as I can offer.
1. A distension of capillary to "noncapillary" sizes.
2. An elementary capillary break.
There is nothing more.

[Summer]

nothing will dry because both sides are in equilibrium with the ambient humidity of the air.
The question was whether the moisture on the cold side (20%) of a capillary flow of warm (8%) at a time when the partial pressure greater than the warm side?.
I think it will not be as I do not see the forces to such a transfer.

[baltazar]

And as for me, I do not know.
1. They took as a wood a laminated pattern. Any adhesive reduces the water vapor permeability.
2. We determined the water vapor permeability across the grain. And the wood has a clear anisotropy of gas and a water conductivity. Across the grain - it is bad, along the grain it is excellent. The gases in the radial direction are well conducted underway.

[buldozer]

It's not even that.
From the inside + 20 and 20% 0f humidity, and in the outside thre are no chances.
Definitely, the water flows and evaporates inside.
I believe 90 percent.
I have a model - wet from a condensation the water pipe.
I close the pipe by the insulation from the blotter.
The steam continues to flow.
Where does the moisture?. Can be vaporized? or
Wil it leak to the pipe?
A partial pressure is one thing.
The force of gravity is the force of a different order.
The capillary forces doesn’t care a gravity.

[Summer]

In general, I want to respond to this question purely instinctively, the moisture in the stump will be aligned, i.e, from cold it will go through the capillaries to warm. I thought so at first. But it is not so.
In the subconscious, we have examples where in our real life we moisten the edge of wood, and after some time, it is fully soaked. But this example is not suitable for an analogy: there is no temperature difference.
Let’s recall what is the reason for evaporation / condensation, It is a thermal motion of molecules. The higher temperature, the greater kinetic energy of molecules.
Now, about the equilibrium moisture content. This is a moisture, where a kinetic energy of water molecules on the surface of cellulose fibers is equal to the energy of vapor molecules near these fibers, and there are no changes in a moisture content.
i.e. on a cold side (-10 to 80%), the vapor energy (Ep1) is equal to the energy of water molecules on the surface of cellulose (Ets1).
And on a warm side (20 40%): Ep2 = Ets2.
But we know that on the warm side, the energy of vapor molecules is greater than in the cold side: Ep2> Ep1 (i.e., the partial pressure is greater)/
Next. and Ets2> Ets1, i.e. energy of molecules on the surface of cellulose is bigger on the warm side, than on the cold side, and a capillary transfer will be sent from hot to cold.

[buldozer]

You are locked on the vapor. And there is not steam. There's a water.
You did not answer, where does the water disappear in my pipe?.
Here is another example.
A cold damp earth.
The water comes up through the capillaries.
How does it go with your theory?
And I would like to finally get not an deduction, but a reference, as it is advisable to the book.

[Summer]

Oh, about the piece of wood, yesterday said a nonsense!. Quickly, I take my words back. It is glued in a longitudinal direction, I did not pay attention to the size of sample. On a diffusion of CO2 it is not affected, of course. However, the paragraph number 2 is in force.
And about the water transfer - there is not any violation of the laws of thermodynamics. We heat the room, make a work and raise the partial pressure of steam inside. It is rushing out, and it is condensed (in capillaries) and merges back to the gradient of moisture. We heat the room once again, etc.
Entering into a wall, the vapor should free evaporate outside not to disturb an existing balance, or if it breaks it a humidity of wall will increase. It will not be able to go out more than it has already evaporated, so the moisture goes inside. The inner side of wall becomes more wet than the air in the room. The drying process begins, the wall comes into the equilibrium again (perhaps with more humidity in the room).
And about the diffusion of gases. In the article, they note very timid the correlation between a moisture transfer and a diffusion of CO2. But it's a known fact that CO2 is highly soluble in the water and at least on the wood, and the oxygen moves exactly.

[constructor]

The idea is good, but unrealistic. How much water should you get forward through the membrane to transport CO2 in the solution?. And what about an oxygen?. The water has only one way- out. What kind of force does cause the water molecules move in the capillary transport along the moisture gradient?.
Where does the energy come from?.
What kind of energy can be expended, except for the energy of thermal motion of molecules?.

[buldozer]

A pipe is the same, only without an outdoor exit.
An analogue of the pipe –is a sealed wall with the insulation inside. Where does the water go?
Drop on the blotter.
Agree, the power is definitely there.
What are their names I do not know. I would call it a capillary diffusion. Probably it is so called.
And the water moves by the capillary action. It moves as long as it will be balanced by the force of gravity or the end of capillary. No more ways - it got up. It dried and then it moves. There are such wetting agents. and a candle works so.

[baltazar]

There are no problems regardless of the season: a supply and exhaust ventilation machine with the recovery is an optimum. What about the walls?. They'll never give a required ventilation, even if the house is completely wooden ...

[Summer]

I have read. A diffusion, a water vapor and a partial pressure ..
He sat with a calculator.
First I figured, what are the pressures in winter.
The vapor pressure of the outside has hundreds of Pa even it happens to 1000 Pa, and more.
O2 (by a change by few percent) has hundreds of Pascal.
CO2 (a change for few percents) has a hundred Pa.
A wind pressure has a dozen Pa.
A thermal head inside-out has Pa units.
It became clear that a heat and a wind pressure are not an obstacle to the vapor pressure from the room.
A diffusion. As I understood is, above all, the process of alignment of partial pressures.
While sitting in the room (closed the window and the door) –I 'm burning an oxygen, and I’m producing CO. A consentration of CO2 increased (the difference between the partial pressures of units, a dozen Pa), it depends on the resistance of walls for the penetration of CO2.
The oxygen content is reduced (the difference of partial pressures has hundreds Pa.).
CO2 goes, an oxygen comes. If the wall has a sufficient permeability, I will not suffocate.
But when I get there, and the process of diffusion will begin in a pure form. A partial pressure of CO2 in the room tends to catch up with the partial pressure of outboard CO2. A superfluous content will get out, and its place will be occupied by other gases – a nitrogen, an oxygen, in the same proportion as in the wall.
In this case the sum of partial pressures inside and outside is the same.