The casing is essentially a protective element in the design of a window or door opening, which ensures the safety of the geometry of the windows/doors. A casing or window frame in a wooden house is a kind of buffer between a heavy “living” wall and fragile glass. The correct casing will last as many years as the house itself.

The need to line openings is determined by the very nature of a wooden house. Let us explain in more detail - the vast majority of log houses/timber houses are built from wood with natural moisture content (that is, no one specially dries the logs before construction). This wood begins to gradually dry out, while decreasing in size. Accordingly, the walls “sit down” in height.

The process of house shrinkage lasts for years. But even after 3-5 years, no one will undertake to guarantee that the openings will not leak in the future. Therefore, since ancient times, windows and doors in wooden houses were installed with casing boxes - they were then called decks.

Painting by Vasily Maksimov “Interior view of a hut”, 1869 - a door surrounded by a log.

Modern casing is a technological thing, perfectly suited for the installation of plastic and aluminum windows, heavy balcony blocks, and metal entrance doors. Let's take a closer look at what types of casing are now popular, methods of its manufacture, and installation scheme in openings.

Types of casing

The classic casing block looks like the letter “P” from the end. Now this form of casing also remains the most popular. In timber houses with thin walls, casing with the letter “T” has become popular. Separately, it is worth highlighting the casing in the embedded (cranial) block. These are 3 main types of casing boxes.

For each of these types, different profile geometries have also been developed - with or without a quarter cut, with a slant, or antique. According to processing methods and purpose, they also distinguish between rough and finishing casing, Euro casing, power casing, arched casing, carriage casing, semi-antique casing, and plywood casing. There are even combined options, when the outer layer of the product is made of valuable wood.

Let us consider in detail each type of casing.

Casing with the letter "P"

The casing box shape has been proven for centuries. Sturdy, reliable. It is most often installed in log houses and houses made of rounded logs. Typically, a quarter is selected from the outside of the casing for installation of a window or door frame.

Requires the formation of a tenon in the wall.

Casing with the letter "T"

T-casing appeared on the market relatively recently, when profiled timber with cut bowls entered the market. At the ends of the openings of such house kits, a groove was already selected from the factory.

T-type is used mainly in timber houses with a wall thickness of 100-150 mm, and log houses made of rounded logs of small diameter. Requires cutting a groove in the wall. In a high-quality T-pipe, the spike is glued into the body, which greatly increases the rigidity of the product. It’s even better when the tenon and the main one are one.

Casing in a mortgage (cranial) block

Defective T-type casing box. The embedding block is usually used at the stage of cutting or assembling a log house so that the openings do not warp. After construction is completed, a wide board is attached to this beam with self-tapping screws, to which the frame (window, door) is attached.

If you use regular lumber from the market (not kiln-dried), then there is a high probability of being remade in the future. Reasons: the block is pinched and bent when the frame shrinks, which causes it to jam in the groove and stops the shrinkage. When the board dries, it warps the frame. The block is pressed against the board only at the points where it is fastened with self-tapping screws - it bends relative to them, and the casing begins to blow through.

From the practice of our company, per year our teams remodel up to 80 other people’s properties, where windows and doors were installed in embedded bars. The photo shows a real case.

Rough casing (for finishing)

An inexpensive option for frames for log houses and log houses where further finishing is planned. All parts of the casing can be made from solid wood or using the adhesive method; polishing of the products is not performed. Profile shape T or P, quarter not selectable. Plastic windows are placed on an installation profile, the window sill is plastic, and the slopes are usually also made of PVC. Inside and outside the opening is finished with platbands.

The window is installed on a plane (without making a groove).

Finishing from solid wood

Must be made only from high-quality and dry wood. Most often from ordinary pine after forced drying, Karelian pine, cedar, larch, KELO cracker. U-type profile shape, with or without choice of quarter. Looks great in hand-cut log houses, houses made of thick logs, gun carriages.

Euro casing (finishing glue)

A popular option for finishing casing (which does not require finishing of slopes). It is made using the glue-type method from dry bars - glued into a sheet (with knots) or into a micro-tenon (without knots). The profile of the euro casing can be P and T type, straight or with an extension into the opening, with or without a quarter.

Antique gun carriage casing

Casing box made from KELO carriage - for high-status houses and baths, hunting lodges. It does not require the installation of platbands - the seam between the casing and the wall is caulked and closed with decorative rope. The visible part of the casing is skillfully aged (firing, brushing). P-type casing profile, options with or without quarter opening, with expansion of openings into the house.

Antique casing (with platbands)

Classic European casing is fired and aged using the brushing method (during processing, the soft fibers of the top layer are removed, the surface becomes rough, but polished). T- and P-type profiles, quarter cuts, and opening expansion are possible. Wooden trims are made in the same style.

Combined casing

The base of the product is made of solid pine, and the top layer is made of a composite adhesive board, which can be made of pine, oak, beech, and valuable wood species. The combined casing successfully combines a reasonable price and aesthetic appearance. The profile of such casing can be P or T type.

Plywood casing

The technology for manufacturing a plywood casing is the same as for LVL timber. The plywood sheets are glued together securely. The tenon in the T-profile can be additionally fixed with self-tapping screws.

The plywood casing can be used as a rough casing (for finishing).

How the casing is installed

In general, the process technology is as follows:

1. an opening is cut in the wall
2. a tenon is formed on the sides of the opening or a groove is selected
3. the opening is insulated with jute tape
4. a wind block is laid at the bottom of the opening and a window sill is mounted
5. risers are installed
6. the top is mounted
7. the free space above the top is sealed with soft insulation

Differences in the installation of door and window casing

The door casing may be missing the lower part - the threshold. In this case, the bottom of the risers is bolted to the lower crown/beam.

The lower part is always present in the window casing. But its appearance may differ. The following options are possible:

• in the rough casing the lower part is not visible. The window sill is usually plastic, matching the color of the frame.
• in the finishing/Euro casing, the lower part acts as a window sill. In this case, the casing can move inside the room and to the sides of the opening, forming so-called ears.

The video shows the entire process of installing a door casing in a timber house (T-type, with the formation of a tenon in the wall):

The technology for installing casing in a timber or log house is the same.

Manufacturing of casing

High-quality casing should be made of dry wood (forced drying in drying chambers, output humidity 8-10%). Boards and timber from the construction market are not suitable for these purposes, precisely because of the high humidity.

Pine wood is most often used, as it is the most common and inexpensive. Spruce is also used. Exclusive options are also possible - cedar, larch, Karelian pine, KELO crackers.

The basis for the solid casing is a carriage with a thickness of 50 mm or more. For P-casing, a carriage of 90 mm is used. The width of the casing board is equal to the thickness of the wall.

The adhesive casing can be with or without knots. In the first case, the prepared bars are glued together on their sides - this method is called sheet gluing. Knot-free casing is assembled from short bars, which are glued together at their ends - into a microspike (looks like a comb).

How to calculate the size of the casing/opening

Let's say that you want to install a plastic window measuring 1 meter in width and 1.2 meters in height in a log house with a wall thickness of 150 mm. At the same time, only technical openings have been cut in your house. Let's do the math.

First, you need to decide on the type and thickness of the casing. For the selected conditions, casing with a T-shaped profile, glued “in-situ”, 55 mm thick, is ideal. The window sill will be plastic, which means the lower part of the casing can be taken with a smaller thickness - 45 mm.

If the frame is installed without a quarter (on a plane), then the width of the cut opening should be 15 cm greater than the width of the frame (1.5 cm for foam, 0.5 for jute, 55 for the riser). The final width of the opening is 115 cm.

With a quarter, the width of the opening will be +12 cm, the total - 112 cm.

What happens if you leave the openings WITHOUT casing?

Answers to the most frequently asked questions

Since wood is a living natural material, a natural process of shrinkage of the logs occurs in a wooden log house after assembly.

As a result, horizontal deformations, torsion and vertical displacement of the rims occur.

To eliminate the destructive effects of drying logs and timber on window blocks, a special installation technology is used, called sash or casing. Its essence is to create a sliding fastening of the window block, in which the shrinkage of the frame does not affect its geometry and integrity.

The casing of windows in a wooden house is done before the caulking work begins. The casing box (casing box) is a durable wooden frame assembled from thick, well-dried coniferous boards. The frame of the frame consists of a window sill, two risers (sidewalls) and a closing top board.

The dimensions of the frame are selected depending on the size of the opening, leaving a gap of 3-5 mm between the side posts of the frame and the wall for laying insulation. The width of the frame boards should be equal to the thickness of the log house walls.

Features of installation of the pigtail

The casing is installed in such a way that when the walls of the log house shrink, its crowns can move freely vertically under the influence of their own weight. To do this, a gap of 40-60 mm is left between the box and the upper crown, which gradually decreases during the shrinkage process, compensating for the vertical displacement of the logs.

Protrusions (grooves) are made on the sides of the casing frame. Under the influence of the settlement of the crowns, the casing frame slides along these guides, eliminating pressure on the window block from the side of the logs.

In addition to protecting window blocks from deformation, the frame (casing) reliably strengthens the ends of the openings and prevents the crowns from falling out under their own weight.

The frame of window openings can be made in two design options: U-shaped (into a deck) or T-shaped (into a tenon).

U-shaped pigtail is performed in this order. A window sill board is placed in the opening and secured to the lower crown with self-tapping screws. Spikes are cut out at the ends of a wooden wall with a chainsaw. The side parts of the casing frame are installed on them, in which grooves are cut according to the size of the tenons. Vertical movement of the logs occurs along these grooves under the influence of shrinkage.

All contact surfaces of the frame with the walls are treated with an antiseptic solution, and a soft compressible insulation is laid between the groove and the tenon (it is prohibited to use polyurethane foam!)

The insulation (flax batting) is fixed to the wood using a construction stapler.

The last stage of installation of the casing frame (frame) in a timber house is the installation of a topper - a board with a thickness of at least 50 mm. It is placed opposite the side posts and attached to them using self-tapping screws.

Installation of a T-shaped pigtail has no fundamental differences from the installation of a U-shaped one. The difference is that not a tenon, but a groove is cut out at the end of the window opening. A groove is also selected on the sides of the casing frame and a wooden block is glued into it, thus obtaining a T-shaped profile of the required size.

The glued block plays the role of a stiffener, ensuring that the geometry of the frame remains unchanged and the wall shrinks evenly.

The casing of T-type windows requires installers to have precise markings, correct fitting of elements and knowledge of important assembly nuances. In particular, if the block is not glued into the side of the frame, but simply screwed to it with self-tapping screws, there is a risk of this structure blowing and freezing. Therefore, anyone who wants to make a window frame with their own hands will do better with a U-shaped casing, as it is easier to manufacture and install.

How to make a window frame correctly You will be prompted by a step-by-step guide that can be found on the Internet or a video that specialized companies post online. However, when assembling such a structure with your own hands, questions always arise. Therefore, we will say a few words about the correct sequence of its installation.

First you need to install a window sill board in the opening, then place one of the side posts on the insulated end tenon, then the top board and the second side post.

It will be useful for owners of log houses in which the processes of drying and shrinking the walls have already been completed to know that the frame in such houses must also be installed before installing wooden or plastic windows.

The fact is that the completion of shrinkage does not mean a complete cessation of the process of changing the size of logs and timber. It is always necessary to take into account the significant seasonal deformations of this material, which without installing the casing will cause distortion and jamming of the windows.

A strong argument for doing window frames yourself with the budget option of building a wooden house, the cost of such work is quite high.

Thus, in the price lists of companies that perform window framing, the cost of this work for a timber house (with cutting and preparation of openings) is 2500-3000 rubles per opening.

For a log house made of profiled timber, it is estimated at 3,800 to 4,900 rubles, and for log houses made of rounded logs, installation of casing will cost the customer 5,000 to 5,700 rubles, excluding the price of the material.

Some contractors price their work on installing window frames in linear meters, although when converted to one window opening, the price turns out to be approximately the same as we indicated above.

Useful video

What is a pigtail and why is it needed?

To avoid disturbances in the openings of a wooden house and to protect future windows and doors from deformation, wooden casings are installed.

The pigtail performs a restraining function, strengthens the tightness between structures, and holds the crowns of the log house.

The casing (window) is made of wood, in the form of a box and then inserted into the window or doorway. The log is held and gives minimal load, the future structure will remain intact. Any casing options must be strong, so a wooden beam is perfect for making various types of casing.

Installation in the opening, regardless of the choice of window frame, is carried out in a house that has been standing for more than a year. Why is this being done?
Everyone knows that a log house must sit for some time in order for the log to shrink. More often, this rule applies to log houses, where logs are selected according to caliber and are preserved in their natural, original form. For the construction of a house, material is used that has natural moisture, as well as material that has already been dried in production. Also, some casing options are used in frame and other houses.
What types of casing are there in a wooden house?

To begin with, casing boxes with an expansion gap are installed. This is due to the fact that wood tends to swell and shrink depending on weather conditions, and this can continue for about six years. At this stage, the selection of the pigtail begins.
Types of casing:
- with embedded beam;
- tenon casing;
- casing in the groove;
And also the types of sockets in a wooden house can differ into rough and fine.

Basic rough casing is used in houses where further finishing is expected. This is a fairly economical option, which involves the further use of finishing materials to create an aesthetic appearance. For rough cutting, edged timber with natural moisture is used.

If your house is made of logs or timber, then in this case you should immediately install a finishing casing. First of all, dry, planed material is used for it. In our online store website you will find all types of wood that you may need to make your own casing.

Let us examine in detail the types of casing.
Casing with embedded timber.
For vertical sliding of the casing, a groove 5 cm deep and wide is cut in the inner side of the log and a block of square cross-section is placed in the groove. Next, they actually assemble the pigtail from a regular straight board and insert it into the opening. All joints are insulated with jute or flax fiber. It is important to leave a gap between the top board and the main block; the distance is approximately 6-8 cm. The casing is attached to the embedded bars and to the lower crown.

Casing in a tenon.
The cross-section resembles the same as in a casing with an embedded beam, only the design is made immediately as a T-shaped one. The installation principle differs in that, first, the T-shaped sides are installed in pre-insulated grooves and pushed apart by the bottom board or window sill, and only then the structure is secured with a top.
The casing in the groove resembles a U-shape. A protrusion is cut out of the log, after which side logs are mounted on it. The protrusions serve as guides along which the casing will move. Further installation, as in the tenon, the principle does not change.
In all cases, leave a gap along the top edge into which to lay the insulation.

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Window casing - photo report on self-assembly and installation

Hello. Today I’ll tell you about how to make a casing for a window in a wooden house and why is this design needed at all? It seems to me that the topic of this article will be of interest to many readers, since houses are built everywhere from logs, timber and other lumber.

Why installing windows in a wooden house without casing is not recommended? A structure made of wood is subject to processes during which the geometry of the walls changes, and therefore a window block without casing sooner or later becomes deformed.

Now about everything in more detail and in order.

Basic information about what we will do

Almost all buildings, with rare exceptions, are subject to shrinkage, during which the walls, under their own weight and the weight of the roofing system, change their configuration. But in wooden buildings such processes occur most intensively, since wood is a living material that changes within six months to a year from the end of construction work.

If you install a plastic or wooden frame into an opening in the wall, you will notice that after a few days the structure will crack and bend. The casing for windows in a wooden house takes on the load from the shrinkage process, as a result of which the frame remains intact.

As an example, consider the arrangement of window openings in houses made of profiled timber with a cross-section of 150×150 mm. The openings are prepared for the subsequent installation of modern double-glazed windows with PVC profile frames.

Assembly technology

The instructions for assembling and installing the casing box are as follows:

• At the initial stage, we mark the window openings with our own hands;

Comment on markup execution! We mark on the wall the perimeter of the window we plan to install. Then we add 50 mm to this perimeter on each side - this is the thickness of the board from which we will make the box. In addition, on each side we add another 50 mm for shrinkage, and, if the house is recently built, we add not 50, but 70 mm at the top and bottom of the opening.

• Using the markings made, we draw the perimeter of the opening, focusing on the water level;

There are already cuts on the wall, don’t pay attention to them, since it was originally planned to install windows of smaller width, but later a different decision was made and the opening had to be re-made to fit different sizes.

• We start the chainsaw and cut right through the wall according to the markings;

In the photo, a chainsaw is used, but if the work is carried out indoors, we use an electric saw.

• Carefully remove the lumber from the cut opening;
• In the cut opening we make markings for installing sliding beams on the sides;
• Based on the measurements taken, we cut the timber so that the length of the prepared parts is 50 mm less than the height of the opening;

For the manufacture of casing, planed dry lumber with a moisture content of no more than 8-12% is used.

• We apply the timber to the opening, position it there according to the spirit level, so that it runs in the center and make corresponding markings with a pencil on both sides of the opening;

• Using the markings made with a chainsaw, we cut out grooves from which we select wood to a depth equal to the width of the timber used;
• We must antisepticize the internal volume of the groove - it is enough to cover the wood with one layer of waste, which will prevent subsequent rotting of the lumber;

• We lay and drive a beam into the prepared grooves on each side of the opening, so that the distance from the top of the beam to the top of the opening is 50 mm;

We drive in the beam, periodically checking its verticality at the spirit level. As a result, the beam should stand strictly vertically and at the same time should not move from side to side.

• While the saw is nearby, we clean the horizontal planes of the opening from irregularities;
• We mark on the board the dimensions of the parts for assembling the casing;
• We cut the boards to the marked dimensions on a miter saw;

• We make grooves at the ends of the two boards that will be located along the width of the opening, namely, we select wood for 1/3 of the board, 50 mm from the end;

The end groove is made as follows. Using a miter saw, a cut is made along the width of the board equal to a third of the thickness of the board. Then the board is placed vertically and, striking with a hammer on the butt of the attached ax, we cut off the excess wood.

• To ensure that the groove is perfectly even and there are no problems when joining frame parts, we process the cut of the board with a router;

• Before we begin assembling the casing, we cover the previously prepared opening with jute tape, which acts as a sealant and as shock absorption, placed between two structures tightly adjacent to each other;

• We install the side elements of the casing according to the level and fix it to the sliding beam with self-tapping screws;

We select the correct length of the self-tapping screw so that it fits into the sliding beam, but does not go right through it.

• Excess jute sealant protruding between the opening and the fixed boards is pushed into the gap;
• In the upper part of the casing, we apply acrylic sealant to the grooves;

• We install the upper spacer in the prepared grooves;

• There remains a shrinkage gap between the spacer and the timber, which we seal and insulate with mineral wool;
• In the lower part of the casing, we connect the sidewalls to the opening using L-shaped fastening hardware;
• We fill all the technological gaps with sealant and at this point the installation of the casing in a wooden house can be considered complete.

How casing works

Now that we know how the casing is assembled, it's time to learn how it works.

During shrinkage processes, the walls of a wooden house change their configuration, namely, both the thickness of the lumber itself and the gaps between them decreases.

Now let’s remember the structure of the casing, which you could see in the photo report. The 50 mm thick expansion gap is designed to neutralize the effects of the shrinkage process. That is, the gap will decrease, but the pressure on the thrust will not increase.

In addition, let's remember about the sliding beam, thanks to it the walls on the sides of the window can change their configuration without in any way affecting the condition of the casing. The lumber on the sides of the opening can move, but since the sliding beam is not directly connected to them, the position and geometry of the window will remain unchanged.

Conclusion

So, you know how to assemble the box yourself and install it in the wall opening. Agree that the work shown in the photo report is not difficult and, if desired and equipped with carpentry tools, many people can cope with such a task.

I propose to talk about your experience in performing certain works in the comments to my articles, I’m sure everyone will be interested. Finally, I recommend watching the video in this article.

Hi all! Recently, good friends approached me for advice. They are building a house from timber and have reached the stage of installing plastic windows. They build, of course, not themselves, but hired teams.

But you still need to control it. They asked me to talk about the nuances of installing double-glazed windows in the house, what to pay attention to, etc., so as not to waste money down the drain and then not have to redo it six months later. We sat with them over a cup of coffee, I told them everything in detail and at the same time wrote it down in this article. Maybe this information will come in handy for you too. Read!

Structures and buildings made of natural wood tend to move, that is, shrink. This characteristic imposes restrictions on the installation of windows and doors in light openings.

If you do not use special techniques in the form of casing or frames, the installed window or door will be deformed, broken, and gaps will appear between the frame and the wall.

To avoid such problems, additional framing of the light opening, which is called casing, is widely used. In essence, this structure is a wooden product - a box that is placed on the walls and to which window and door profiles are attached.

This simple design ensures the independent position of windows and doors relative to the walls, and therefore, when the house begins to sag, the casing becomes mobile - it moves along the opening, moving the frames with it without deforming them.

There are two options for making a pigtail, or rather its profile. Highlight

• tenon-groove - where grooves and tenons are cut out in the parts being fastened for joining and fastening;
• monolithic, or finishing, which also have a tongue and groove, but the counter part of the beam is made of solid wood timber. In this case, laminated veneer lumber is not even recommended due to the characteristics of the glue’s reaction to changes in humidity.

It is important that when making one type of casing or another, it should not sit tightly on the walls of the house in any case, since in this case mobility will not be ensured.

Since the frame consists of sidewalls, a top and a bottom (or threshold), it is very important to leave a larger gap between the top and the wall - up to 12 cm, which is intended to compensate for the shrinkage of a wooden house. Such gaps, of course, are processed: they are insulated and closed with platbands.

In order for the casing to serve for a long time and reliably, before installation it is important to treat it with an antiseptic and follow the installation order: first the bottom, then the sides and finally the top with insulation and platbands.

Types of pigtails:

• Photo 1 – Finish (with a quarter).
• Photo 2- Power “SPIRE” or “GROOVE”.

The difference between the two options is the slope for a PVC window

Vocabulary and material for the pigtail:

Carriage (side posts) - timber material, according to the thickness of the house timber (deck):

• Minimum 150mm*150mm(100);
• Maximum 360mm*150mm(100);

Top (upper part of the pigtail) – 150 mm*50 mm;

Insulation:

• flax batting (jute);
• mineral wool;

Antiseptic – protection of wood from exposure to atmospheric and biological factors;

Measurement of window frames (house wall thickness 150 mm) and PVC (plastic) windows.

• Distance from the floor 80-90 cm.
• The width of the casing is 12-14 cm greater than the width of the window.
• The height of the casing is 14-18 cm greater than the height of the window.
• Installation of a frame and a plastic window.
• Preparing the opening to fit the size of the frame.
• I cut “SPIRE” or “GROOVE”.
• Antiseptic treatment.
• Roll seal (flax-wadding (jute)).
• Installation of the CARRIAGE (the side parts of the pigtail) is carried out without fastening elements (screws, nails)
• The top (top part) is put on the side elements.
• The upper gap of the window frame is 8-12 cm. At the rate of 10 cm per 1 p/m of window.
• Laying insulation (mineral wool) + steam-waterproofing on both sides.
• Installing a PVC window like in a box (the gap is filled with foam).

Source: plastikovokna.ru

Installing windows in a wooden house is significantly different from installing windows in brick and stone houses. For example, the openings of buildings made of logs and beams, as a rule, have a quarter, but not from the inside, but from the outside.

Shrinkage

But the most important difference between houses made of wood (does not apply to frame-panel houses) is the ability to shrink as a result of drying of the wall material (logs, timber).

And this point is decisive in installing plastic windows in a wooden house, because if you install a window, as usual, in a bare opening, it will inevitably be crushed and deformed by the shrinkage process.

There is an opinion that the first two are the most active period of wood drying. But that's not true. After the construction of the house, the shrinkage of the walls continues for decades. But that is not all. Wood not only gives off moisture, but also absorbs it. Therefore, rigid fastening when installing windows in a wooden house is impossible in principle!

• Shrinkage in a log house is about 10 – 15 mm per log D = 250-300 mm
• Shrinkage in a house made of timber is about 7 – 10 mm per beam with a section of 150x150 mm
• Glued laminated timber – unknown.

There are other ways to calculate the shrinkage height of log houses as a percentage: approximately 10-15% of the original height. But in fact, the shrinkage of houses made of timber and logs depends on many factors:

• on the material (log, rounded log, timber, laminated timber);
• on the time of material procurement (winter procurement or summer);
• depending on the time of day (morning, evening) Yes-Yes!!! Don’t be surprised – we explored this too!
• from the environment where the forest grew (swamp, field); on the degree of resinity and density of the tree;
• on the size of the material - both its length and thickness;
• from the moisture content of the material;
• on the size of the building; on construction technology (dowel, type of felling, etc.);
• from the material of inter-crown insulation; from the type of wood;
• depending on the time of year when construction is carried out.

The most severe shrinkage occurs in log houses made of ordinary logs, followed by rounded logs, profiled beams, timber, and laminated veneer lumber.

Even if the house is more than a dozen years old, it is still necessary when installing windows in a wooden house to take into account the vertical movements of the walls as a result of an increase and or decrease in humidity and air temperature at different times of the year.

Wooden house – Living

A wooden house is a constantly moving structure, compared to buildings made of stone and concrete. Therefore, the installation of windows in a wooden house is carried out not in the opening itself, but in a special wooden box, which acts as a connecting link between the window and the wall. This box is called differently: casing, frame, deck, pigtail, linden.

How the pigtail works

As can be seen from the photo, the casing is an ordinary window box made of four, sometimes three (sides and top) thick boards, installed inside the opening.

The meaning of this design is that it is independent of the vertical movements of the wall and moves freely in the opening, since it is not attached to the logs (timber) with nails, screws, or other fasteners, but is held in place by grooves in the side posts mounted on the spikes at the ends of the logs.

Even foam is not used to seal the gaps around the window frame - only tow, jute (flax batting) and other soft insulation.

Shrinkage gap

Please note: a large gap is specially left above the jamb, the size of which is designed for the maximum possible amount of shrinkage of the logs (beams). During the first years after the construction of the house, this compensation gap will gradually decrease to a minimum, but the upper log (timber) of the opening, if calculated correctly, will not press down or deform the frame.

Thus, the shrinkage of the house will not in any way affect the size and shape of the window frame, and, accordingly, will not damage the plastic window located inside it.

Shrinkage gap size

If you decide to install windows in an old wooden house that has long gone through the process of shrinkage, then, when disassembling the window blocks, you will probably notice: they are made according to the same principle as the casing design described here, i.e. are not nailed to the logs of the opening, but are fixed in it using a simple “mortise and tenon” system on the sides.

This suggests that the technology of installing windows and doors in a wooden house in frames was invented a very long time ago, and is used successfully to this day. We will not invent anything new and will follow the same path.

There are several ways to install the pigtail:

• T-shaped frame - a groove is made at the ends of the opening logs, and a T-shaped profile is placed into it;
• U-shaped - a tenon is cut out at the ends of the opening logs, and a groove is made in the side casing posts).

We do both options, since they provide maximum strength and stability of the opening, because the frame not only protects the window from shrinkage of the walls, but also ensures the stability of the wall at the place where the opening is cut.

Briefly, the sequence of our actions will be as follows: we cut out an opening in the wall, the dimensions of which are slightly larger than the dimensions of the inserted plastic window;

Preparing the opening for installing a window in a wooden house

Before cutting, we mark the window opening using a level, because the plastic window will be installed strictly level in all planes, therefore the frame must also be installed in the opening as accurately as possible according to the level initially.

The lower crown in the opening needs to be sawed through so that a flat horizontal platform is obtained.

We determine the dimensions of the opening based on the size of the plastic window, the thickness of the casing bars and the size of the required gaps.

We perform all calculations visually. Here is an example of a diagram for calculating the size of the opening for a rough T-shaped frame:

Accordingly, we take a beam with a cross-section of 100x150 mm and cut out a T-shaped profile.

The size of the shrinkage gap (H shrinkage) is not easy to determine, since the amount of shrinkage of the house, as mentioned above, depends on many factors. If we, for example, roughly calculate, taking everything to the maximum, then for a window with a standard height of 1400 mm (plus the thickness of the casing crossbars, plus installation gaps ~ 245 mm) with 15 percent shrinkage, the top gap will be 24.5 cm - a huge hole , the height of which will most likely end up being too large.

To simplify the task and avoid mistakes, you should not rack your brains over GOSTs that regulate the shrinkage values ​​of building materials of various wood species, comparing this with local climatic conditions, etc.
You can do it simpler, namely:

• If you are building a new house, then start installing windows in it no earlier than a year after the construction of the log house in order to wait out the period of the most active shrinkage. Then, when manufacturing and installing the frame, the size of the shrinkage gap (H shrinkage) can be safely made 60-50 mm for a log house, 50-40 mm for a timber house and 40 mm for a house made of laminated veneer lumber;
• if your house has stood for more than five years, then the shrinkage gap (H shrinkage) can be made minimal - 40 millimeters, just to compensate for possible seasonal changes in the geometric dimensions of the opening;

So, we calculated the size of the opening, marked it and cut it out. Now you need to cut out a tenon at the ends of the logs (beams) on the sides of the opening. The tenon is also marked using a level in the center of the log (beam).

Making a pigtail

First, you need to decide on the width of the frame bars: it should either be equal to the thickness of the wall, or be a little larger, so that later, when installing external trims, they (the trims) fit tightly and unhindered on the frame, and not on the wall. There is another option in a log house - a groove around the opening along the width of the groove.

Secondly, to make a pigtail you need to take well-dried material, otherwise the assembled structure itself will soon deform as it dries.

First we cut out the bottom part (window sill), making it 10 cm longer than the width of the opening. At the ends of the window sill we cut a groove for a tenon 65 mm wide and 40 mm deep.

We also make small 20 mm recesses at the ends of both window sills for joining the crossbars with the side posts - the so-called locks.

We make the side posts 70 mm higher than the height of the plastic window frame. On the reverse sides of the racks, using a circular saw, we cut out a groove for a tenon 60 mm wide and 40 mm deep. We immediately make a lock in the side posts for the upper part.

Lastly, we make the top part of the pigtail. Based on the dimensions obtained between the two installed side parts.

Installation of the pigtail

We begin installing the frame into the opening from the bottom crossbar (window sill). Then the top is inserted into the opening, under which we place the side posts one by one, placing them with grooves on the tenons.

We fasten the elements of the frame together with self-tapping screws and, if desired (not necessary), coat the joints with sealant. We caulk the gaps around the casing with ordinary tow, but without much fanaticism, so that the parts do not bend.

We close the upper shrinkage gap with soft insulation such as Rocwool or holofiber. This operation is best done after installing windows and external trim.

Now you can begin installing the window.

Installing a window in a wooden house

We install a wooden or plastic window, aligning it with the front edge of the frame. There is no need to place a window inside a third of the wall thickness, as is done in a panel or brick house, due to the lower thermal conductivity coefficient of wood (smaller freezing depth).

Moreover, given the small thickness of the walls of a wooden house, by deepening the window into the opening, we will be forced to trim the already narrow window sill. And the ledge that is formed as a result on the outside of the opening will have to be additionally closed and sealed.

And as measurements taken with a thermal imager show, the main conductor of cold is the profile itself. For more details, see the photo report based on photographs from a thermal imager here.

Rough frame for cladding

If you have calculated the dimensions of the opening and the frame as described above, then the installation gaps around the window frame when installing in a wooden house should be 15 mm on the sides, 15 mm on the top and 15 mm on the bottom (we do not make the bottom gap larger, because the stand profile makes it possible later place a plastic window sill under the frame, the thickness of which is 30 mm).

It is more convenient to attach the frame to the frame with the help of self-tapping screws of such a size that they fit into the body of the frame, but do not penetrate the wall. We drill holes in the frame with a drill with a diameter of 5-6 mm. Using self-tapping screws longer than the thickness of the frame is dangerous because they will pass through the frame and screw into the logs (timber), which is unacceptable.

Provided that all preparatory work has been done using a level, the window frame should fit exactly along the frame, i.e. the front edge of the frame should be parallel to the plane of the window, without noticeable distortions.

Waterproofing a window from the outside

Before foaming the gap between the window and the frame, we need to decide what material we will use to waterproof the installation seam on the street side. As you know, the two main enemies of foam are sunlight and water.

If we can simply cover the installation seam with platbands or flashings from the sun's rays, then with waterproofing the situation is more complicated, because it must meet two basic conditions: not let water in and at the same time not prevent moisture vapor from escaping from the inside to the outside.

Well, and, of course, waterproofing must be resistant to prolonged weathering.

All these conditions are met by materials such as PSUL, waterproofing vapor-permeable tape and special sealant “STIZ-A”.

Sealant "STIZ-A" - a one-component, vapor-permeable acrylic sealant of white color for sealing the outer layer - is characterized by good adhesion to the main building materials: plastic, concrete, polymer concrete, foam concrete, plaster, brick and wood, among others.

It is also resistant to UV radiation, precipitation, temperature deformation and can be applied even at temperatures as low as -20 degrees.

The only disadvantage of this material is that it is difficult to find in small containers, and buying a whole bucket makes sense when you are installing a lot of windows. If you choose “STIZ-A” as external waterproofing, then the procedure will be as follows: first we foam the window, then, after complete drying, we cut off the foam sticking out from the outside and after that, using a spatula, apply sealant to the cut.

Waterproofing vapor-permeable tape (self-adhesive butyl rubber tape consisting of a vapor diffusion membrane with an adhesive layer of sealant on one or both sides) is sold in rolls of different widths.

In our case, a tape with a width of 70 mm is suitable. When using this tape as waterproofing, ensure it is oriented correctly when gluing.

You can determine this by blowing into it from one side and the other (don’t forget to remove the paper first). Since there is a membrane inside the tape, air passage is only possible in one direction. The side from which it is impossible to “blow through” the tape is the outer (street) side.

The sequence of actions (first the tape, then the foam or first the foam, then the tape) does not matter much, but you need to take into account that the foam, expanding when drying, not only stretches the tape with a bubble (it will interfere later when installing platbands), but in general it can tear it away from the window or frame.

Therefore, if you first stick the tape, then screw the platbands or hard strips on top of it immediately, and only then foam it. Or foam it first, wait for the foam to dry, cut off the excess and stick the tape on the same day so as not to expose the foam cut to prolonged weathering.

PSUL is a pre-compressed self-expanding sealing tape (similar to foam rubber), impregnated with a special composition, thanks to which it is waterproofing and vapor-permeable. Supplied compressed, rolled into rollers.

If you choose PSUL tape, then buy one that expands more than 30 mm. The PSUL will have to be glued not to the outer side of the frame profile, but to the end next to the front edge.

This should be done after fixing the frame in the opening, but before foaming. Of course, it is more convenient to cover the frame with PSUL before installation, when it lies on the floor, but then the installation will have to be done at an accelerated pace, because after a few minutes the tape will expand and interfere with work.

The installation seam should be foamed only after the PSUL has completely expanded and closed the installation gap. But here the same problem is quite possible as with the waterproofing tape: the foam expanding as it dries can squeeze the PSUL out. This can be avoided by pressing the PSUL on the street side with platbands or flashings.

Internal vapor barrier of windows

On the inside, the foam should also not remain open to prevent moisture from entering it from the air in the room.

To install an internal vapor barrier, you can use vapor barrier tape, which has already been discussed in the main section of this site, or use acrylic sealant SAZILAST-11 (“STIZ-B”).

The vapor barrier tape is glued to the end of the frame with a thin adhesive strip before foaming. Immediately after foaming, the protective paper is removed from the wide adhesive strip, and the tape is glued to the pigtail.

Before the foam under the tape hardens, it is advisable to immediately install the window sill and screw the starting profile to the edges of the frame, otherwise later the tape “bloated” with foam will interfere with this.

Sazilast is applied to the hardened foam, or more precisely, to its cut. In this case, it is no longer necessary to rush to install the window sills and the starting profile, as when using tape. Nothing will prevent you from doing this later, when it is convenient.

Interior decoration

The interior decoration of a window in a wooden house (window sills, slopes) is not much different from the decoration in a panel or brick house.

It’s even a little simpler here: you don’t need to drill holes to install the slopes - we fasten everything with self-tapping screws into the wood (into the frame).

There is also no need to additionally insulate the slopes from the inside with foam plastic or other material. To be on the safe side, before installing the slopes, it is enough to foam the inner surface of the casing with a narrow strip next to the installation seam. This will be enough, because wood does not freeze as deeply as concrete or brick.

How to make slopes has already been described on the pages of this site. I want to propose a slightly different method of finishing a window in a wooden house, or rather, refuse to install a plastic window sill and any panels, and instead use the window frame itself.

A window sill, like a window sill and slopes

This method of installing a window in a wooden house allows you to save on slopes and window sills, gain time and achieve, in my opinion, a greater aesthetic effect, but for this you will need a good woodworking machine to evenly cut out the so-called reverse quarter on the casing elements, which will be install a plastic window.

What a reverse quarter is can be easily understood from the figure. This is the recess into which the window frame will be installed on the street side.

Quarter depth – 20 mm. The width is made exactly corresponding to the thickness of the frame, for example: a 5-chamber VEKA has a profile thickness of 70 mm, therefore the width of the reverse quarter should be 70 mm.

It is important to accurately calculate the dimensions of the frame and the window, carefully assemble the frame and install the frame in the opening exactly at the level - the internal clearance should have the shape of a regular rectangle, and all edges of the outer edge should be located in the same plane without distortion.

In order not to make a mistake in the dimensions, it is better to first make and install the window frame, and only then accurately measure and order the plastic window locally.

Installing a quarter window

Let's assume that the window frame is already installed in the opening. The size of the plastic window is made such that it is slightly larger than the “clearance” of the casing, or more precisely: 10 mm more in width and the same amount in height.

Such a window will not fit into the frame from the inside, but it will easily fit into the reverse quarter from the street side. In this case, the edges of the frame will “hide” behind a quarter of 5 mm on each side (this is no longer possible - the sash hinges will interfere), and an installation gap will remain around the frame, which will later be filled with foam.

The frame is attached to the frame with self-tapping screws, as already described above. To ensure a beautiful tight connection between the frame and the casing on the room side, you can use a D-shaped door seal. It is glued before installing the frame with the adhesive side on the edge of the quarter. Accordingly, the dimensions of the quarter must be adjusted for the seal.

But as practice shows, with high-quality production of the pigtail, the need for such an addition disappears. The window is placed directly into the quarter and the meringue of the gaps is pressed tightly against the frame.

When attaching the frame, we press it tightly against the quarter, squeezing the seal, and screw in the screws, fixing the window in this position. The installed window is foamed from the street. Then, after the foam has dried, its excess is cut off, the seam is sealed with waterproofing tape or sealed with “STIZ-A” sealant, and the trim is installed.

Of course, since we refuse to decorate the casing with any additional elements, we must refine it, i.e. give it a look that matches the interior design of the room.

First of all, you need to give the bottom crossbar the shape of a window sill so that its inner edge protrudes slightly from the wall and is slightly wider than the opening.

Secondly, we “dawn” the internal surfaces of the racks and the top, i.e. we abandon the primitive rectangular (in cross-section) shape of these elements and create a large chamfer, simulating a reversal of the slopes.

Next, we process the inner surface of the casing elements. There are many options here: texture, color - the choice is yours. You can simply sand the surface and coat it with varnish. You can cover the wood with stain of the desired color so that the surface of the casing is in harmony with the color of the window and/or the color of the walls.

There is also, in my opinion, an interesting, but more expensive option - brushing the surface, i.e. antiqued treatment.

Artificial aging of antique wood is now very popular in various design styles. The essence of brushing technology is to remove soft fibers from the surface of wood using a metal brush (along the fibers), while the surface turns from smooth to embossed. After giving the relief texture, the wood is cleaned of lint and fibers, then the final gloss is given.

You can immediately coat the wood with varnish, but “aged” wood will look much more impressive after treating it with stain of the color you want. However, there is an even more effective way of painting - patting - creating a contrast between dark wood pores and a lighter surface.

This is achieved using paint of the desired color: the entire front surface of the casing is covered with it, and then the top layer is removed with a cloth before the paint has had time to dry. The final stage of artificial aging is varnishing. It is applied in two or three layers. You can then rub the surface with a soft cloth to add shine.