Correct vapor barrier
Moisture in the vapor state is present everywhere - this is part of the natural water cycle. Ignoring this factor while ensuring the energy efficiency of buildings and structures is unacceptable. It is known that overmoistening reduces the thermal resistance of wall materials to 30%.Today, the is the right vapor barrier - an important part of the thermal protection of the building site.
Why is it correct? Because the vapor barrier, which does not meet the standards or installed incorrectly, leads to the loss of properties of the insulation layer in a year. The accumulation of moisture on the surfaces of the structures starts the process of their destruction. This applies to any materials.
The need for steam protection
There is one more question: do you need steam protection in general? It depends on many factors. The calculation itself is made with the help of SNiP 23-02-2003, devoted to thermal protection of buildings. The main data for it are the construction of the wall, floor, floor or other surface, as well as the climatic conditions of the region.
This calculation is also important because foreign manufacturers of vapor barrier materials calculate its permeability and strength for warm - compared with our - winters. And since the vapor barrier works only in the cold season, the hardest frost will be the exam for the material.
And only materials certified for our conditions are capable of withstanding it. Yes, the vapor barrier with its own hands makes it possible to significantly reduce the cost of this process, but not at the expense of the quality of the materials.
For example, cheap Asian films contain plasticizers, which significantly reduce its adhesion to the adhesive base of fastening tapes. This means that after a while such a pseudo vapor barrier will consist of separate fragments of this material.
Requirements for steam protection
- The vapor barrier layer must meet the following requirements.
- Provide design resistance to vapor permeation at a thickness of not more than 4 mm.
- Have a heat resistance that does not allow the material to "slip" on vertical surfaces at temperatures up to 50 ° C.
- When exposed to positive and negative temperatures, maintain design resistance to vapor permeation and adhesion to connecting tapes or insulated surfaces.
- Keep elasticity, be continuous and vapor-tight in the joints.
The material must have a packing instruction.
Types of steam protective materials
- Pergamum and roofing material. Traditional materials are sometimes used today. Mounted on a flooring of boards or OSB boards.
- Polyethylene reinforced film. Used as vapor barrier in saunas, swimming pools and bathrooms.
- Polypropylene reinforced simple and anti-condensed viscose layer. It absorbs moisture, preventing its condensation. With the onset of the warm season the moisture evaporates. These films are durable and not expensive.
- Diaphragm or "breathing" membranes. The most perspective kind, allows to "breathe" a heater, does not suppose penetration of a moisture to it from within. Does not require air gaps, can be one- and two-sided.
- Special materials: reflective films with aluminum coating, foamed polyethylene with aluminum foil - penofol.
Conditions for effective steam protection
Like all construction work, the vapor barrier device begins with preparatory work. The heat insulation material must be dry. Surfaces must be cleaned of dust and dirt, seal up the cracks, align to fit closely the roll vapor barrier material and fixing its rails.
Absolute impermeability - the correct vapor barrier , this is the basic requirement. A vapor barrier is tested on the serious objects with the help of the airfield, which creates a low pressure.
The places where cable harnesses and vent valves are introduced are the weakest place. Not a hole embedded in a diameter and a few millimeters, and the installation of the vapor barrier does not justify itself. In full accordance with the laws of physics, this is where all moisture from the room rushes.
The vapor barrier layer of the film material the manufacturer always selects and indicates the correct orientation of the film during installation.
Where it is necessary to arrange a vapor barrier
Steam protection is used to protect structures and insulation on surfaces that serve as a barrier between a heated and unheated room.
- Attic, attic and basement rooms, floors.
- External walls of heated premises.
- Bathrooms, swimming pools, saunas and saunas, kitchens.
In this list, you can include other surfaces bordering between warm and cold air. Exceptions can be built of timber: the wood itself the correct vapor barrier and is able to absorb excess moisture. There is no condensation on it.
Wooden floor protection
is required for the wooden floor above the unheated basement, underground, or other unheated volume. It is always arranged from the side of the heated room.
The lag is laid on the overlap with a step of 600 mm, the heater is tightly packed between them, and already on the logs there is a vapor barrier material. On it also the finishing covering is laid.
When installing a wooden floor on concrete slabs, before installing the lag, the surface of the concrete floor is covered with hydroprotection with careful sealing of the joints.
Ceiling protection
Here the correct vapor barrier of the ceiling includes two layers of steam protection: on both sides of the heater. Modern films such as "Izospan" provide a vapor barrier of insulated roofs. A special very strong film is attached to the rafters from below and prevents moisture from entering the under-roof space.
Wall structure protection
An important building protection step - is the correct vapor barrier of the walls, both from the outside and from the inside. When warming the walls inside the room, the film is attached over the insulation, inside the room. Strips of material are glued with a tape, the frame is additionally pressed by a counter-rack, on which the inner finish is fixed.
On the external surface of the wall, the vapor barrier insulation installation is similar: the film closes the insulation from the outside and an external finishing material is arranged along the pressure rails. The film is attached from below upwards, 100-200 mm film is produced on the plinth to protect the wall abutment to the plinth.
Orientation of the vapor barrier material
All listed works do not require special qualification, but sometimes the vapor barrier by the hand is performed in violation of the manufacturer's instructions of the material. If the film on both sides has the same structure and color, then both sides are considered working.
When the sides are different, you need to carefully study the installation requirements. The rule, which side to lay the vapor barrier , is general: if the film has a smooth and rough surface, then the rough side - it will retain moisture - is located outside, and smooth - to the heater. The reflecting surfaces of the film always look outward: their smooth side faces the heater.
Laying of the vapor barrier
Before purchasing the vapor barrier material, it is necessary to clearly identify which structures need protection. There are a lot of its kinds on the market, so it is important to determine the required one precisely. Only in this case it will be clear, how to properly lay the vapor barrier and provide maximum protection.
In most cases, it should prevent the penetration of moisture to the heater, so special attention should be paid to the joints. A reliable fastening of the film to the base provides fastening with a wide bonnet or furniture staples.