Why are the walls of most houses insulated... how not to

I will write available. I use just a couple of unusual construction terms. Even if you're not building, the phenomenon of improper insulation is worth watching!

So, we live in a village under construction, in a village. During the walks, we observed who was insulating the walls.

Because they were built on their own. They delved into everything, what, how and why to do. As a result, atUS frame wall, half a brick of silicate outside - 40 cm of penoizol - half a brick of red inside.

This is how the process of pouring with penoizol looked like:

The big picture

About the rest of the houses. The most popular is insulation between an expensive facing in a half-brick and a gas silicate block. It can be mineral wool, basalt slabs, expanded clay, polystyrene and its brothers. Usually 5 (!) Cm layer. Maximum, in one house with expanded clay, a gap of 10 cm was covered.

Why is it wrong?

There is a rule in construction textbooks that the vapor permeability of wall materials should increase from the inside out.

Let's look at the table of vapor permeability coefficients of some building materials:

This means that such a standard cake as a gas silicate block - mineral wool - brick has vapor permeability coefficients: from the inside to the outside 0.2 - 0.3 - and bam, bummer! — 0,11-0,15

Styrofoam is even worse: 0.2 is a bummer here! — 0,03-0,05 — 0,11-0,15.

Maybe there are better insulation materials for such a construction? No. For expensive polystyrene foam - 0.02-0.03, for polyurethane foam - 0.05.

People tried to leave an air gap in this place, and there the dressing fittings quickly rusted. Because it's not right!

Why do they do as they do?

Because the neighbor has the same.

How do you like the logic?

Why not

There is such a tricky thing - the plane of capillary moisture. It is always there, it shifts from the seasonal temperature.

For example, this plane was between polystyrene foam and brick. What's next? A new life begins, of fungi and other microorganisms. In addition, moisture from the atmosphere or from the home accumulates in porous building materials and destroys them.

And if the plane of capillary moisture inside the mineral wool turns out to be, then the wool becomes wet. Why is that bad?

Here's a warm sweater. Very warm. We feel warm in it. And suddenly he became wet. Will it be warm in it? No way. The same thing happens with the mineral wool, which is not located where it should be. It also crumbles, sags. And how long would the sweater have to dry inside the wall? So it is with mineral wool, and basalt slabs, and ecowool.

Forgotten, but in vain

There is such a wonderful thing as ventilation.

When my daughter was remodeling her room into a kitchen, they forced us to make an exhaust ventilation in the wall for approval. This is a miracle! Draws out all odors in 5 minutes, windows and a hood above the stove are not capable of this. They themselves would not have done it, because there was no experience.

I will return to the houses of our village. There is some kind of ventilation system in every home. Plus airing, drafts, cracks. All this together and compensates for the incorrect construction of the walls. Partially, because there is no full ventilation! Because it's expensive and ugly, plus extra pipes on the roof. And... it does not come to mind at all! After all, no one has.

Important clarification

Non-porous insulation cannot be placed inside. Example. An acquaintance bought a house with 5 cm of mineral wool in the walls. The house was being built for sale. He began to live - it's cold! Without hesitation, I covered it with expanded polystyrene from the inside. He boasted. Only his thermos house became quickly wet inside. The moisture did not come out. I began to think about full ventilation. I don’t know how it ended.

How can you

In frame structures (we have) the plane of capillary moisture inside the insulation.

Imagine our 40 cm of penoizol and somewhere inside the plane of capillary moisture. Nothing critical. The main thing is that the brick does not deteriorate and the house is kept warm. This will go to poverty. It will be similar with foam glass in a frame house. If the layer is made large enough.

The famous Canadian frame frames, this tree - from 13 cm glass wool - is a tree. It's the cheapest way. Other heaters are also used.

In terms of vapor permeability, it turns out 0.06 (across the fibers) - 0.3-0.6 - 0.06, i.e. not properly. Therefore, Canadians have powerful, expensive ventilation systems. The steam does not go into the walls, it goes into the ventilation. As far as I remember, for the ventilation system there were 500,000 rubles per house, now inflation is more expensive.

So, I'm not saying anything new, just what the Canadians left off. But what in our country is called a skeleton frame according to Canadian technology, without serious ventilation, completely wrong houses. Why? Because everyone does it. Cheaper.

There is an option with ventilated facades, which is very popular. The main thing is that the insulation is dry. This is no longer a wall, but a special protective structure is obtained.

Your opinion on the problem is interesting!

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