How to measure a window for plastic windows. Do-it-yourself measurement of plastic windows? Easily! Measuring the opening for a plastic window in a brick house

Before starting an excursion on preparing windows for installation, on how to properly measure the openings and eventually install these same windows, I would like to say that there is a standard for plastic windows. This standard contains section D (recommended), which just describes the procedure for installing plastic windows. You can get acquainted with this section in more detail by studying GOST 30674-99 - in fact, a document regulating the manufacture and installation of plastic windows.
Unfortunately, this document does not step by step instructions from start to finish, how to install windows according to GOST, but there is only final result. Our article was just created in order to tell you step by step how to mount plastic window and about possible features during its installation.

The period of the year is favorable for the installation of a plastic window

You already guessed what will be discussed in this paragraph. No, we do not mean to say that winter period construction stops and everyone is waiting for warming. But, it is during the warm period that you can comfortably mount a window, engage in the restoration of slopes using wet work (application cement mortars), polyurethane foam has the highest yield and stuff like that. Of course, it is better to mount windows in the warm season. And let's say more, according to technology, it is impossible to put plastic windows in cold weather! (below -10 degrees Celsius).
As a result, improper installation can affect the quality of work, and hence the quality performance characteristics windows. In this case, it makes sense to wait for a warm period in order to still put the windows as expected and not suffer later with distortions, crevices, adjustments.

Measurement of openings for installing a plastic window

You will need a tape measure to measure. Correct measurement is the first step to successful installation of PVC windows. If the measurement is made in a panel house, then everything is simple here, the measurement is made from the intersection lines of the slope planes and walls.

Measuring the opening for plastickno for panel houses.

The peculiarities of the openings of panel houses is the L - shaped section that holds the window in the wall. When measured in panel houses it is necessary to pay special attention to the size of the opening from the side of the apartment. Inside, we measure the distance between the side slopes along the top and bottom, as well as the height from the window sill to the upper slope on the right and left.
The window sill must have a width = wall thickness - window profile width (60mm) - distance from outer wall up to L - shaped step in the wall + ledge (5-100mm).

Measuring the opening for a plastic window in brick house

In the case of measuring for the installation of windows in a brick house, it is important to determine the border bearing wall, that is, with beginning brickwork. Here, the plaster on the slopes can be of considerable thickness, it is for this thickness that an amendment should be made, of the order of plus to the size of 1-2 cm. Inside, we measure the distance between the side slopes along the top and bottom, as well as the height from the window sill to the upper slope on the right and left. Outside, we measure the width of the opening from wall to wall from the top and bottom, as well as the height from the tide to the top of the opening on the left and right. Measurements outside and inside are necessary to determine the possible angle of non-prependicularity of the window slope relative to the wall.
The window sill should have a width = wall thickness - 50 mm. 50 mm is left for finishing the outer slopes.

Measuring the opening for a plastic window in a wooden house

In a wooden house, the window opening has parallel slopes and is actually measured in the same way as for brick house. It is also worth noting that in the case of replacing old wooden windows with new ones, openings are often expanded in secondary wooden housing, since plastic windows are “warmer”. In this case, when installing the window, you will need a benzo or electric saw to change the geometry of the opening.
The window sill should have a width = wall thickness.

The dimensions of the window and its accessories after taking measurements

In most cases, after comparing the measurements from the top and bottom, from the right and from the left, there is a discrepancy between the results. This is due to the distortion of the existing opening, especially in panel houses. For window size calculations, a regular rectangle with the same opposite sides equal to the smaller value of the measured opening from the outside, the smaller size will guarantee the passage of the window into the opening, without destroying the load-bearing elements of the wall.
As a result, taking into account the existing factors, plaster, old frames, etc. should aim for the following:

The width of the window should be 30-40 mm less than the width of the opening relative to the "power" slopes;
- the height of the window should provide a gap between the lower slope and the window equal to the thickness of the window sill (standard plastic window sill has a width of 20 mm) + clearance for the installation of the base bar (30-40 mm) + guaranteed clearance, as for the width (30 mm). Total about 80-90 mm.

After these measurements, you can order a window, window sill and fasteners. On average, it takes 8-10 days to manufacture and deliver a plastic window, major cities- megacities 3-4 days.

Preparations for the installation (installation) of plastic windows

remove everything from the windowsill, remove the curtains, clear the way to the window, provide access to the power supply, prepare garbage bags, cover the floor and furniture with cloth or thick oilcloth.

Removing old windows

After you have waited for your window, you can proceed to dismantle the old one and install a new one. Dismantle without destroying the frame old design very difficult, as it is a labor-intensive and correspondingly lengthy process. Most often, after dismantling, only the sash remains intact. I take them off the hinges first. Sawing down the middle old frame and knock her out of the opening.
We are preparing a place for a new window. We remove the sashes, dismantle the frame, the old ebb and the window sill. The opening is cleared of debris, old insulation, large protrusions of the wall slopes that stand out to the outside, affecting the parallelism of the walls. If, on the contrary, deep depressions and delaminations are found in a brick and panel house, then it would be better to restore the wall first and only then continue installing the window. You can not wait for the complete hardening of the cement, but initially achieve at least filling the cavities with it.

Installation (installation) of a plastic window

Compliance with technology is a guarantee correct installation window. Based on the conditions for the use of professional polyurethane foam, air temperature should be from - 10 to + 30 ° С, ideal conditions for the use of foam is considered a temperature of + 20 ° C and humidity from 60 to 80%. Depending on the size of the window, we calculate the volume of foam. The weight of one cylinder should be 850-920g. with a foaming agent content of 750 ml. Manufacturers promise a foam yield in the range of 45 - 50 liters, but it is necessary to take into account the volumes to be filled. With the condition of inhomogeneity and a large number irregularities, you can count on filling 15-20 liters with one cylinder. At the same time, you will need a gun for mounting foam, PSUL tape (along the outer perimeter of the window), vapor barrier (along the inner perimeter assembly seam). Also: level, plumb line, perforator, drill and nails corresponding in size to the dowel (more often used, 8x60)
The sashes are removed from the plastic window and the double-glazed windows are removed. In more detail, about how to remove double-glazed windows in the article "Replacing double-glazed windows in plastic windows". Do not forget to mark all the glazing beads of the removed double-glazed window in order to put them exactly in the same place in the future. During the production process, the glazing beads are determined locally with a special ruler and a slight mismatch (1-2 mm) will be noticeable at the junction of the horizontal and vertical glazing beads.
From the outside of the window unit box is removed protective film, PSUL tape is glued. This is a vapor-permeable sealing tape that looks like foam impregnated with a special composition. That allows you to protect the mounting foam from exposure to the sun and moisture from the street. At the end of the plastic frame is glued vapor barrier tape, to protect the mounting seam from the inside of the room from moisture.
Bearing pads are installed in the opening, they will take the main weight of the PVC structure. They are aligned to the level and height of the corresponding box to be installed. Install the box on the pads in a tight fit to the outer opening. You set the frame on a plumb line with absolute axial symmetry and a thin end (often the quality of the level does not allow you to deduce the correct position). Then, using a perforator, drill a hole through the profile of the window block box into the wall to the depth of the existing nail dowel. Most often, 4 holes are made, two each on the right and left sides of the box. It is necessary that the dowel nail enters the wall through the box before pressing the head against the box. But without fanaticism, when the head is pressed against the box, it begins to deform noticeably under the applied efforts and turns from a rectangular into an oval.

There is another way to fix the box, using fixing plates. They are also, two by two, installed on the edges and then fixed in the wall. Depending on the type of window system available, appropriate iron plates are purchased.

After that, the box stands on its own blocks and corresponds to the set level.

Please note that the holes for the condensate outlet must go to the drain, and not to the window opening

The gaps between the wall and the box are foamed with foam. If the volume is large, it is better to lather in several approaches. This will depend on the density of the application of the foam, taking into account its drying. Pay attention to the outer part of the window, if the PSUL tape somewhere does not adhere to the wall or simply lags behind, such a place must be covered with sealants. There should not be an empty opening or gap between the window frame and the wall with outer side. We are waiting for drying.

The window sill is cut out under the appropriate opening in width and length. The window sill protrudes into the room by 5-10 cm, and to the sides of the window opening by 5 cm on each side.

...and is attached to special grooves on the box,

with a slight slope from the window, but strictly horizontal in level. When choosing the width (depth) of the window sill, it should be taken into account that the window sill is "sinked" by 2 cm under the window frame, so the width of the installed window sill will be 2 cm less)

The ebb is screwed to the box with the help of self-tapping screws, previously cut out under the opening.

We begin to install shutters and double-glazed windows, taking into account that the first glazing bead is attached from the top, in order to prevent the double-glazed window from falling.

Window installation always begins with measuring the window opening. This procedure is the most important: the overall quality of the installation will depend on the correct measurement.

For this reason, it is recommended to entrust this procedure to professionals. But it doesn’t hurt to know how to measure windows correctly, because this, at a minimum, will help you determine how experienced the window installers are, and whether you should think about contacting another, more competent organization.

What are the consequences of incorrectly measuring the window opening?

Not properly taken dimensions window openings often lead to considerable problems. For example, the window frame may be larger than the opening, and this is an additional cost for expanding this very opening. Smaller windows are no less of a hassle. As a result of their installation, gaps may appear that will have to be filled with mounting foam, or the issue can be resolved by increasing the slopes. Again, extra costs, both time and materials.

In addition, such a window is unlikely to cope well with the functions assigned to it: to protect an apartment or house from cold air, precipitation, etc.

It is worth noting that from different types window openings depends on the approach to measurement. We will talk about this further.

How to correctly measure window openings with a "quarter"?

Professionals say that it is most difficult to measure window openings with a "quarter" (photo 1). In this case, we mean openings that have a protrusion of ¼ of a brick of the outer perimeter. This ledge is necessary in order to protect the structure from falling out.

So, how to properly measure windows that have such a ledge. When measuring, it is important to take into account that usually these “quarters” are not symmetrical, their sizes may differ: for example, distortions are possible, both vertically and horizontally.

When measuring a window, experts always follow the main rules (so that there are no unnecessary problems during the installation process):

the size window frame should be such that it goes beyond the side "quarter" by about two to four centimeters, i.e. the frame should be wider;
the frame should go beyond the upper wall of the opening no more than one and a half to two centimeters;
the window sill timber is made one or two centimeters higher than the lower wall of the opening: this is necessary for the trouble-free installation of the ebb.

The figures show in detail how the window with a "quarter" is measured.

Figure 1: Measuring the width.

A - the width of the window along the slopes from the outside (we add 4 cm to it);

B - the distance between the points where they will adjoin the frame internal slopes;

D - actually, the width of the window;

C is the width of the opening from the inside.

Note: after measuring, it must be checked that the width D is not greater than the distance B and the width C.

Figure 2: Height measurement.

E – window height without substitution profile;

F is the height of the opening from the base to the upper slope (outside); 1-2 cm is subtracted from it for the gap, and 2-3 cm is added to enter the frame beyond the "quarter" from above;

G - height of the substitution profile

H is the height of the window, taking into account the substitution profile.

How to properly measure a window without a "quarter"?

The presence of a "quarter" at the window opening is not always found. Such protrusions are usually not made in panel and wooden houses(photo 2).

Naturally, such openings require a different approach to sizing. Let's name the basic rules for measuring such windows:

when measuring the opening, it is taken from its width from 2 to 10 centimeters to leave space for mounting seams;
there is usually only one horizontal gap - from above; its width varies from 3 to 6 centimeters.

General rules for measuring windows for all types of openings

It is important to remember when measuring the window and the fact that the frame during installation should not rest against the opening, it should be slightly smaller. This gap, called the mounting gap, is necessary in order to leave room for natural expansion of the structure. According to the rules for installing plastic windows, the seam can be from 2 to 5 centimeters.

When measuring windows, it is important to remember that measurements should be taken both indoors and outdoors.

When determining the width of the future window, we measure the opening from the top, middle and bottom, and choose the smallest value. From this number, the distance to the gaps is subtracted, the resulting value will correspond to the size of the frame. The height is also measured at several points (left, middle and right), and the distance required for mounting gaps and a substitution profile is also subtracted from the smallest value. The resulting difference is the height of the future horse.

Window measurement technology only seems simple. In order to prevent unnecessary errors, it is best to entrust the measurement of the window opening to professionals who can correctly calculate the frame dimensions even for the most non-standard openings.

Before removing the size of the window, you need to find out the features of its opening and configuration. It is recommended to approach measurements very carefully, since in panel houses the dimensions window structures approximately the same, and in brick buildings - may differ by several centimeters. We suggest using this manual if you want to install metal-plastic windows. You also need to know how to measure pvc window to roughly determine how much the windows will cost.

Window Measurement Rules

Measurement of the window of the house must be made from the street and from the side of the dwelling. Both dimensions are required to determine the depth of the window opening. You need to know that the window must be no smaller than its size. outer part. And how much more, this is what we should calculate.

Remember that the opening can be skewed, this is especially noticeable in panel houses, so you need to increase the size of the structure by the amount of skew. After you determine the dimensions of the window, you should compare them with internal dimensions opening. This will allow you to find mechanical errors in the calculations that you made earlier, and then evaluate what kind of plaster should be in order to apply it to internal slopes.

Before measuring the window size, make sure you have the following tools at hand and prepare: a measuring device, pliers, a blunt chisel (15-20 mm), a building level, a small hammer, a pencil, a ruler, an elastic band, a blank for result records. It is convenient to measure using a tape measure or a telescopic ruler. The measurement accuracy should be 10 millimeters.

Measurement of windows in a residential building with a quarter

Window openings in houses that have a quarter should go outside the top and side slopes by 20-30 millimeters. This should be taken into account if you decide to seriously approach such an issue as window metering. The width of the window should be measured along the outer slopes, it is to it that 40-60 millimeters are added to enter the window on both sides in a quarter or slightly less if the wall is curved.

After measuring the width between the outer slopes, the result should be checked that it is not greater than the distance between the points at which the inner slopes are adjacent to the frame. The width of the window frame should not exceed the width of the inner opening.

If during the check the width of the window turned out to be larger, then you need to contact professional measurers. The height of the window is the distance from the base of the opening to the upper slope, minus 10-20 millimeters, which falls on the gap for the mounting foam, and plus 20-30 millimeters, which is necessary for the structure to enter the upper quarter.

If you plan to use a stand profile when installing windows, which is a prerequisite for arranging a window sill and a low tide, then you should reduce the height of the window by another 30 millimeters (the height of the stand profile). Now you know how to properly measure a plastic window in a building with a quarter!

In order to check the correctness of your work, check the following dimensions: the height of the window frame without a substitute profile should not exceed the distance from the window sill to the upper slope from the inside. The height of a window with a support profile should not exceed the length between the lower edge of the window sill and the upper inner slope.

Measurement of a window opening in a residential building without a quarter

Measure the height and width of the window opening before measuring the plastic window. When measuring the width, measure at the top and bottom of the opening, take the smallest value in subsequent calculations. It is necessary to subtract 20-40 millimeters from the width of the opening (gaps for foam on both sides), and this is what we will consider the width of the plastic window.

The height is measured from the right and left sides of the opening. From the smaller indicator we subtract 20-40 millimeters (gaps for foam) and 30 millimeters (height of the stand profile). This will be the height of the window.

Window width measurement

To obtain the size of the window, add 3-5 centimeters to the width of the slope from the outside (slightly less in a situation of wall curvature). To accurately measure the window, you need to know some of the nuances:

the window should be the same or slightly wider where the frame touches the slopes;
the design should be smaller than the inner opening of the window.

In order not to make mistakes when measuring windows in non-standard openings, you need to contact a specialist. The measurer, who is a professional, can identify the causes of discrepancies on the spot.

Window height measurement

The scheme for measuring a window in height is quite simple and understandable to every developer. In order for the design to go into the upper quarter, add 1.5-2.5 centimeters to this size. When installing a window with a window sill and a low tide, you need to use a stand profile, and subtract 3 centimeters from the resulting size.

In fact, window design is determined by the color and configuration of the existing window. Products should be, if possible, the same on the facade of the building. When designing a structure, you need to take into account some practical advice and technological limitations:
the specified sash dimensions in the window system catalog should not exceed the maximum;

due to the limited capabilities of the perimeter fittings, the width of the tilt-and-turn sash should not be less than 400 millimeters;
the diameter of the bend of the semicircular arch should reach 520 millimeters;
the dimensions of the openings can be different due to the arrangement of the floor and other factors, so the measurement is done during the construction and reconstruction of the building, and all dimensions are consistent with the project.

Thus, you have learned how to properly measure windows in residential buildings with a quarter and without a quarter. There is a method for calculating height and width. Prepare all the tools necessary for the job in advance so that you don’t interrupt the process! So you can determine the cost of the future metal-plastic construction.

Before measuring the size of the window, you need to find out what features the opening has and its configuration. It is advisable to approach the measurements with all care, because. panel houses have approximately the same size of window openings, and houses built of brick can have a difference in window openings of several centimeters. If you want to measure and install metal-plastic windows yourself, we recommend using this manual in order to find outhow to measure a plastic window. It is also useful to learn how to measure window openings in order to approximately understand how much a window will cost, and after that proceed .

How to properly measure a plastic window

The window must be measured both from the side of the street and from the side of the dwelling. Both dimensions will be required to calculate the depth of the window opening. You need to know that the window must be no smaller than its outer part. And how much this value will be more and you need to calculate.

You need to remember that the opening may be skewed. Especially such distortions are noticeable in panel houses. In this regard, it is necessary to increase the dimensions of the structure precisely by this amount of skew. After the dimensions are determined, they must be compared with the internal dimensions of the opening. This analysis allows you to identify mechanical errors in the calculations that you made earlier, and then evaluate what kind of plaster should be for processing internal slopes. you can read in the corresponding article.

Before starting measurements, you need to prepare the following tools that will come in handy in the process of work: tape measure, building level, hammer, pencil, ruler, pliers, chisel, sheet for recording measurement results. The measuring accuracy must be 10 mm.8

Measurement of window openings - width

In order to get the size of the window, it is necessary to add 3-5 cm to the width of the outer slope (slightly less than in a situation with a curved wall). However, in order to make accurate measurements of the window, you should know some of the nuances:

- The window must be exactly the same or slightly wider in the place where the frame touches the slopes.

- The entire structure must be smaller than the size of the internal opening of the window.

In order not to make mistakes when measuring windows in non-standard openings, you should still contact a specialist. A professional measurer will find the reasons for the discrepancies on the spot.

Measurement of window openings - height

After the window has been measured in height, it is necessary to subtract 2 cm from the distance from the base of the opening to the upper outer slope. The distance that needs to be taken away will be required to fill the space with mounting foam.

The scheme for measuring windows in height is quite simple and should be understandable to everyone. In order for the structure to enter the upper quarter, 1.5-2.5 cm must be added to the result.

Measurement of window openings in a house with a quarter

In houses that have a quarter, window openings should go outside the top and side slopes by 20-30 mm. This must be taken into account if you are serious about this issue. The width is measured on the outside. It is to the width that 40-60 mm is added to enter the window from two sides into a quarter, and when the wall is curved, then a little less.

Measuring window width

After measuring the width between the outer slopes, the results should be checked to ensure that they do not exceed the length between the points where the inner slopes meet the frame. The width of the frame must not exceed the width of the inner opening.

If measurements were taken, and the width of the window came out larger, then it is advisable to contact professionals. And for plastic window repair It is not necessary to call professionals.

The height of the window is the distance from the base of the opening to the upper slope minus 10-20 mm, which gives the necessary clearance for the foam, and plus 20-30 mm, which allows the frame to enter the upper quarter.

window height measurement

To install a window sill and a low tide, there is one prerequisite, a stand profile must be used. In this case, the height of the window must be reduced by another 30 mm, which is occupied by the stand profile.

To check the correctness of the calculations, you can check the following dimensions: the height of the frame, excluding the stand profile, should not exceed the distance from the window sill to the upper slope inside. And the height of the frame, taking into account the stand profile, should not be more than the distance between the lower edge of the window sill and the upper slope from the inside.

Thus, windows are measured in a building with a quarter.

Measurement of window openings in a house without a quarter

Before measuring window openings, you need to measure the height and width of the opening. When measuring the width, the measurement must be made at the top and bottom of the opening, and in subsequent calculations, take the smallest value. From the resulting opening width, 20-40 mm should be subtracted, which are necessary for gaps for mounting foam on both sides. This size will be considered the width of the window.

Determining the window width without a quarter

Determining the height of a window without a quarter

L, H - size for a box of window blocks;

A, A 1 - dimensions for the clearance of window openings;

E, E 1 - dimensions for mounting clearances;

P - height for the stand profile;

K - size for the lower mounting gap

Height must be measured on the right and left sides of the window opening. From the obtained smaller value, you need to subtract 20-40 mm (for foam) and 30 mm (for the stand profile). As a result, we get the height of the window.

During the measurements, it is also necessary to measure the deviations of both the horizontal and vertical parts of the wall and the frontal plane. These recommendations are shown in the figures..

The design of windows, in principle, is limited only by color and its configuration. If possible, you need to make sure that all products are the same on the facade of the building, and also ensure the convenience of window care. When designing, the following practical recommendations and technological limitations should be taken into account:

- The limited possibilities of perimeter fittings oblige to carry out a tilt-and-turn sash with a width of at least 400 mm.

- The diameter of the bend of the semicircular arch should be 520 mm.

— The size of the openings can be different due to the influence of many factors. In this regard, measurements must be taken during the construction or reconstruction process, and the resulting dimensions must be consistent with the project.

Video. How to properly measure a plastic window

Summarize. You have learned how to correctly measure a plastic window in houses with a quarter and without a quarter. There is a method for calculating the width and height. Think ahead and prepare all essential tool, in order not to be distracted by the search in the process. Thanks to the obtained measurements, you can easily calculate the cost of future metal-plastic structures.

If you decide to replace the old wooden windows modern plastic structures you need to order first finished products according to your measurements. Therefore, before ordering, it is necessary to take all measurements from the window opening. This work should be approached very carefully, because not only appearance of the future window, but also the possibility of carrying out its direct functions (heat, moisture and noise insulation). Therefore, further it will be considered how to properly measure a plastic window.

General information on the correct measurement of windows

Measurement of a plastic window must be carried out both from the outside and from inside. This is necessary in order to be able to determine the depth of the window opening. Quite often a situation arises when, during measurements, it turns out that the opening is slightly skewed. This happens especially often in panel buildings. In this case, it is necessary to increase the dimensions of the product by the size of the skew.

After you have measured the dimensions of the window opening from the outside, the resulting values \u200b\u200bmust be compared with its internal dimensions. This will allow you to see possible inaccuracies in the calculations, as well as to assess what the lining of the internal slopes should be.

Most window openings have ledges to prevent the window from falling out. These ledges are called quarters.

Ideally, the ledge size is 6.5 cm (1/4 of a brick), but this is only in theory. In practice, the size of a quarter may differ from this value both up and down, and sometimes there may be no quarters at all. Often there are situations when, on the one hand, the protrusion has one meaning, and on the other, another. When taking measurements, such inaccuracies must be taken into account.

The best option is the situation when the plastic window is installed in such a way that:

It was 1.5-2 cm above the edge of the lower quarter, so that it was possible to install a drainage system under the frame.
It went beyond the side ledges by 2-4 cm.
It went beyond the upper ledge by 1.5-2 cm.
The window frame did not touch the walls of the opening, that is, there should be a mounting gap between them equal to at least 4 cm from the bottom and 2-5 cm from the top and sides. In this case, the maximum size should be no more than 6 cm, but in some buildings where the protrusions have big size, mounting clearances may be greater than 6 cm.

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How to make a window measurement for an opening with a "quarter"?

The window opening is measured in width and height. In the first case, the measurement starts from the outside (Fig. 1, A). In this case, one should take into account the entry of the window for a quarter of 15-25 mm. Based on this, about 30-50 mm should be added to the width of the outer slope, which will be the required value.

Figure 1. Measurement of a window for an opening with a "quarter": A - outer side; B - size with external slopes; C is the size of the window opening.

Width plastic product should not be less than the distance between the quarters, and ideally a little more, that is, it is necessary to ensure that the edges of the window rest against external slopes(Fig. 1, C). At the same time, care must be taken to ensure that its width is not over size opening (Fig. 1, C).

To correctly measure the window height, it follows from the distance between the base of the opening and extreme point subtract 20 mm from the upper protrusion. This is done in order to create mounting seams into which the foam will be blown. After that, 15-25 mm must be added to the obtained value. This will ensure that the plastic window rests on the upper ledge.

If it is planned to carry out installation with a low tide, then 30 mm should be subtracted from the obtained value, because in this case it will be necessary to allocate space for the stand profile. In the case of using a stand profile to create a mounting seam, the dimensions of the window should be 30-70 mm smaller than the opening.

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In this case, the process is somewhat different. First, the window opening is measured at several points along the width, from which the smallest value is selected. Then 2-4 cm are subtracted from the resulting width (depending on the width of the window and the evenness of the opening). Height is measured in the same way. In this case, 2.5-4 cm are subtracted from the obtained value.

It should also be possible to install a visor and ebb from the outside to drain rainwater. With this in mind, the lower edge of the plastic window should be higher than the outer edge of the window opening.