The second vapor barrier error

The second mistake is that the vapor barrier was laid on both sides of the insulation and the wooden floor ⠀
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How to vaporize a wooden floor in a wooden and frame house? Immediately, we are talking about the overlap between two residential and constantly heated floors. ⠀
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🗣 On some sites they write that the first layer is laid between the finishing ceiling of the first floor and the draft floor of the second. On others, that on the rough floor and on it immediately insulation. It turns out the vapor barrier will be on both sides? ⠀
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You can’t do this! ⠀
💭 To answer these questions, we reason logically. ⠀
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In frame walls and ceilings, vapor barrier is installed where there is a temperature difference. Those. the room where plus is insulated from the street where it is cold. ⠀
🖇 In the interfloor overlap, between two heated floors, there is no sharp temperature difference. Therefore, water vapor entering the insulation does not condense. ⠀
Hence: mineral wool insulation laid in a wooden floor between the first and second heated floors is rather needed not for thermal insulation of the structure, but for soundproofing the floor. ⠀
That is, in fact, you can do without films, but the living room must be protected from possible particles of insulation in the air. ⠀
But, do not forget that in the house, beside the residents, there are constant sources of moisture and water vapor - a kitchen, a bathroom and a toilet. ⠀
💦 Water vapor, due to the pressure difference, will tend to get from a warm room to a cold zone - through walls to the street, or from bottom to top, to a cold attic through ceilings. Or in the under-roof space, when it comes to the insulated attic. ⠀
We offer such a "pie": ⠀
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🔸Clean and draft ground floor ceiling finish ⠀
🔸Vapor barrier ⠀
🔸 Heater ⠀
🔸 Vapor-permeable diffusion membrane ⠀
🔸 Black and fine finishing of the floor of the second floor ⠀
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In addition to the classic work in the “pie” of overlapping, the films will not let the insulation dust. ⠀
With this arrangement, water vapor will freely come out of the ceiling and the structure will “breathe.” ⠀
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⚠ Important! Do not lay vapor barrier on both sides of the insulated wooden flooring. ⠀

Ошибка при гидроизоляции

Waterproofing Error

The main mistakes in the installation of vapor and waterproofing films and membranes ⠀
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First mistake - wooden beams wrapped with vapor barrier ⠀
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If you study the topic of vapor barrier films and diffusion membranes, a paradoxical situation arises. The more a developer reads, the more he gets confused. Cause? A huge amount of conflicting information from different manufacturers and builders. The situation is aggravated because There are dozens of materials with different technical specifications on the market. ⠀
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🗣 People write that if you close the beams on top with a vapor barrier, then, in the place of contact with the film, the tree will not “breathe”. This will lead to moisture accumulation. Is it so? Or is it better to lay drywall on completely exposed beams, then vapor barrier and only then lay mineral wool? ⠀
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Tell me, wooden beams can be wrapped with vapor barrier, provided that part remains visible in the interior. In my opinion, the film prevents the exit of water vapor from the wooden floor. Or, am I misunderstanding something? ⠀
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@energo_doma recommends cake: ⠀
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🔸 Open wooden beams visible in the interior ⠀
🔸Wooden flooring ⠀
🔸Vapor barrier, with gluing overlays and wall abutments стен
🔸 Frame insulation ⠀
🔸Top insulation - dust and windproof material that releases water vapor. Moreover, there is no need to chase expensive branded films. It is enough to use inexpensive domestic non-woven materials ⠀
🔸 Wooden scaffolds on the frame for free movement in the attic and routine inspection of the roof space ⠀
🔸In the attic, according to the insulation, it is not recommended to lay a continuous flooring ⠀
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💭 "Wrap" wooden beams can only be vapor barrier with variable vapor permeability, the so-called a film with adaptive properties, which, with increasing humidity, passes water vapor. ⠀
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This vapor barrier can only be used over rooms with normal humidity, and not over bathrooms, toilets and kitchens. ⠀
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⚠ Important! If the vapor barrier is normal, then it is impossible to go around the beams with this film, because it will “block” the steam, which will lead to moisture accumulation and rotting of the wood.

Ошибки при гидроизоляции

Third vapor barrier error

The third mistake is the refusal of a moisture and windproof film to block the cold attic ⠀
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🗣 I finish making a cold attic ceiling. Overlap insulated. I know that first they install a vapor barrier and only then, between the beams, lay mineral wool. And how to close the insulation from above? The manufacturer's booklet says that you need to install a waterproofing vapor-permeable membrane. Why is it needed there? Maybe just a cheap hydro or wind protection spread? ⠀
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energo_doma: The manufacturer correctly recommends closing the insulation on top with a waterproofing material - a membrane that allows water vapor to pass through but prevents moisture from entering the insulation. Remember that membranes have their own characteristics. First of all, pay attention to vapor permeability. It varies up or down. ⠀
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🗣 Membranes are usually mounted on pitched insulated roofs close to the insulation. Those. water flows down them and does not linger on the surface. And if you lay the membrane horizontally, it will not leak? ⠀
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energo_doma: If you are afraid that a horizontally laid superdiffusion membrane will leak or let water through because of a roof leak, choose a material with a higher water resistance. The simplest and cheapest vapor-permeable membranes have low water resistance. Therefore, they are laid obliquely, because Still water through them will sooner or later seep into the ceiling. ⠀
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As a result, we got the following pie of a cold attic, bottom-up: ⠀
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🔸 vapor barrier ⠀
Доски blackboards ⠀
🔸 heater ⠀
🔸 moisture- windproof membrane ⠀
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⚠ Important! In a cold attic from above, cover the insulation with a vapor-permeable moisture-proof membrane, which will additionally protect the insulation from wind and moisture, and you from inhaling particles of stone wool.