- Features of the shrinkage of a wooden house
- The role of a jig in a wooden house
- Types of okosyachki
- Insulation of the casing frame
- Window installation
The technology of installing plastic PVC windows in a wooden house differs from the traditional one. Compared to brick or concrete, wooden houses are subject to shrinkage to a large extent. Therefore, the installation of a plastic window differs in the preparation of the opening, and even in the sequence of operations.
Features of the shrinkage of a wooden house
All houses settle, putting pressure on the ground – more stone, less wood. The correct selection of the type of foundation, taking into account the characteristics of the soil (including its heterogeneity, the depth of groundwater, the nature of the upstream, etc.) allows you to minimize the effect of precipitation on the geometry of the structure.
Shrinkage of the house is a consequence of changes in the size of the building materials themselves.
It manifests itself especially strongly in the first years of operation of wooden houses built from a log or a bar of natural moisture. Therefore, the installation of windows in a new house is carried out when it has passed the “active phase” of shrinkage, and this is from 6 months to a year (depending on the tree species, region and cutting season, type of material, etc.). But then shrinkage continues, but much less.
Minimum shrinkage for laminated veneer lumber, slightly more for chamber-dried lumber. In new houses from such materials, windows can be installed immediately, after the construction of the walls and the arrangement of the roof..
But in any case, when installing windows, these features of wooden houses must be taken into account..
The role of a jig in a wooden house
The peculiarity of the tree is that it reacts unevenly to changes in its own moisture. The longitudinal dimensions (relative to the location of the fibers) are almost unchanged. A change in its own moisture affects the transverse dimensions – its natural decrease leads to drying out.
Therefore, when a wooden house shrinks, the height of the wall and the vertical size of the window opening decrease..
To prevent the plastic window from crushing or jamming the movable sashes, it is installed in a special wooden frame – a window, or casing.
The effect of shrinkage is compensated for by two factors:
- “Sliding” way of mounting the window in the opening;
- the gap between the upper board of the window frame and the upper crown of the window opening.
In addition, a dry board is used for cutting, which practically does not change its longitudinal dimensions..
Types of okosyachki
So that the casing frame moves freely during the “drying” of the crowns, and at the same time does not fall out, it is fixed in the side ends of the opening according to the principle of the sliding connection “thorn in the groove”.
Important! The side posts of the casing frame should not be rigidly attached to the wall.
First option. The easiest way to make a profiled side post is to use two elements: a foundation block and a board.
The grooves are cut in the side ends of the opening. The length of the embedded bars must be less than the height of the opening by the amount of the expansion gap, according to the size of the section, they must move freely in the grooves.
The casing box is hammered together in advance. The bars are laid in the spikes, and the box is rigidly attached to them with screws.
Lack of a box – the gap between the bars and the side boards of the box (albeit small).
The disadvantage of this method is that it is difficult to get into the embedded bars with screws (you can split them, or “flash” sideways on the end of the opening).
Second option. The same arrangement of pins and grooves can be observed when making a casing frame from a profiled bar and board. The grooves are still cut in the opening, and the spikes are cut in the side posts of the casing. For this, a bar is used, which is given a T-shape in section. Technically it is more difficult, but there are no slots and fasteners in the casing frame itself.
Another difficulty is assembly. It is carried out at the place.
The third option has a “mirror” profile in comparison with the previous ones: spikes in the side ends, grooves in the sidewalls of the window.
When assembling in place (the second and third options), at the top and bottom boards of the casing frame at the ends, you can cut a spike or groove, which “cling” to the profile.
Depending on the installation method of the window itself, the inner profile of the window can be with a quarter or smooth.
Insulation of the casing frame
Since the casing frame must move relative to the opening, the thermal insulation of the slots in the joint of the tongue-groove and the upper expansion gap is carried out with an inter-crown insulation. As an exception, you can use polyurethane foam only to connect the bottom board of the window, which is rigidly attached to the opening.
The plastic window is installed in the casing according to the general rules and observing the same clearances. We told you about this in the article “How to install a plastic PVC window with your own hands”.
The only difference is in the order – first, the window sill is mounted, and then the frame is attached.
Important! When installing the window, it is necessary to ensure that the lateral fastening of the window profile to the casing is not through.
When foaming a window, the assembly seam is protected from the penetration of water vapor from the side of the opening and the room with a vapor-tight film, and from the street side – with a moisture-resistant vapor-permeable membrane (so-called warm installation).
Window trim with platbands protects the seam from the influence of climatic factors and the destructive effect of solar ultraviolet radiation (plus decorative function).