How to install a plastic window sill. Do-it-yourself window sill installation: photo and video instructions

The final stage of window installation is the installation of the window sill. This process is ridiculously simple, however, it is quite easy to make a mistake. In our instructions, we will show with examples how to properly organize the connection of the window sill to the window frame, carry out the sealing and prevent freezing of the lower zone.

Selecting the type and size of window sill

Despite the fact that the products of most manufacturers of additional components for PVC windows are well unified, there are several types of plastic window sills. However, perhaps you will prefer window sills made of natural wood, artificial stone or veneered countertops? We will also consider such options, but remember that often the choice of product specific type dictated not by whim, but by obvious necessity.

For example, consider two types of plastic window sills - with and without an edge at the back. On the one hand, a window sill without an edge allows you to freely vary its depth and even tolerates oblique cuts, which can correct flaws in window installation. However, in this case, it may be necessary to mount it from the outside through a stand profile, but not all windows have it and it is not always convenient to dismantle the external ebb for fastening. Otherwise, plastic window sills are almost identical except for one feature - thickness. The larger it is, the correspondingly higher the strength of the window sill and its greater protrusion above the plane of the wall is allowed.

Plastic window sills are usually sufficient to meet most needs, but it is worth considering the benefits of other materials. Mostly laminated chipboard and artificial stone slabs are used where you need to add a special twist to the color. “Non-plastic” window sills have no other advantages - they are afraid of moisture, dirt and ultraviolet radiation. However, one nuance still remains: if it is necessary to arrange a solid window sill for several windows, as is the case when installing glazing for a bay window, a continuous curvilinear contour can only be created with the help of a window sill-tabletop.

As for the sizes, everything is simple and obvious with them. The length of the profile must be at least 6 cm greater than the distance between the slopes at the widest part. The depth should provide a protrusion above the wall plane of at least 30 mm, and if there is a radiator under the window, “cover” it with a margin of 5-10 mm.

Preparing the installation site

The opening must be prepared in a certain way for the installation of a window sill, and for each individual installation method, the preparation will have some differences. Let's start with what is the same in all options: we apply to vertical posts square, aligning the edge along the lower edge of the frame profile, and draw two horizontal lines on the slopes that limit the hem. Along the lines you need to make cuts using an angle grinder and a diamond disc to a depth of about 10-15 mm, if available plaster corner at the corner of the slope it should be cut completely. Next, use a chisel or an old chisel to select pockets with a depth of about 30-50 mm in the slopes. More is possible, but it should not be less than 30 mm, otherwise the connection of the side plugs with the angle of repose will be incorrect. If the slopes will be covered with panels, the protrusion of the window sill beyond the slope should correspond to the width of the closing corner profile.

If instead of easy plastic profile a heavy tabletop will be installed, you need to prepare the bottom plane window opening. First, a plaster beacon is installed under the side of the frame, close to the stand profile, on the tubercles of cement mortar. The distance between the edge of the lighthouse and window frame must exactly match the thickness of the window sill-tabletop. By the lighthouse cement mortar a smooth horizontal edge of the opening is drawn on which the window sill will rest, internal corner It is advisable to strengthen it with a plaster corner.

Don’t be surprised, but it also happens that a window is installed without a support profile. If in this case a window sill with a thickness of 18 mm or more is installed without a trailing edge, it is necessary to increase the thickness of the bottom foam seam to at least half the thickness of the window sill profile used. Also, in the lower part of the slope, a series of vertical notches are made in the wall, 30 mm wide, 20 mm deep and about 120-150 mm high. Notches must be made in increments not exceeding 80 cm and at least two pieces per window sill.

Window sill fastening

Unlike common practice, the window sill does not necessarily need to be secured through the frame profile with self-tapping screws. In some cases, this will only cause harm: metal rods serve as excellent cold bridges.

Most correct scheme installation is ridiculously simple: the window sill rests on the stand profile, then incompressible pads are installed under it, for example, mounting wedges, retreating 2/3 of the total depth from the front edge. A small protrusion of the frame above the stand profile allows you to adjust the projection of the window sill above the wall plane, if window frame for some reason it turned out to be deployed. With this installation method, the mounting foam firmly connects the window sill with the opening, while tightly filling the entire space from below.

The window sill without a support profile is fastened using the rear side, which fits tightly into the installation groove in the lower part of the frame. It is only important to clear the foam seam a little and cut off the edge on the sides, otherwise you will have to cut the slopes deeper. Window sills of increased thickness without an installation side have a longitudinal groove like dovetail. Light mounting plates are inserted into this groove, which are used for preliminary alignment of windows. To correctly install the window sill, supports are paved under its rear part with wedges, then the window sill is laid in place, the plates are bent and secured deep into the notches in the wall, which ensures that the end of the profile is tightly pressed to the frame.

Sealing the lower zone

The main trick when installing a window sill is to correctly form the foam seam underneath it. The only exceptions are tabletop window sills, which are attached to the prepared opening plane using liquid nails.

In general, for correct installation a number of conditions must be met:

The lower shelf of the opening was cut down with a slight bevel towards itself, dust-free and moistened with water.
Incompressible pads are placed under the window sill; when you press on the front edge of the profile, it is pressed tightly against the bottom of the frame and maintains a strictly horizontal position.
From above, the window sill is pre-loaded with a weight of about 20 kg per meter, the oppression is distributed along the entire length using a board.
On the sides, the upper plane of the window sill rests against the notches on the slopes.

Then everything happens extremely simply. The entire space between the window sill and the shelf of the opening is filled with polyurethane foam of the appropriate climate regime, with the exception of areas located behind the slope line. You need to blow out the foam under low pressure, using an extension tube to fill the narrowest areas in the back near the frame. After blowing the foam, the window sill should remain loaded until the polymerization of the foam is completed - about 1-1.5 hours.

Sealing cracks in walls and slopes

After the foam has completely hardened, its excess must be cut off. If the foam has been squeezed into the area beyond the slope line, it must be dug out to a depth of at least 20 mm. Under the window, the foam is removed with a chisel or scraper to a depth of about 10 mm. All formed cavities are moistened with a strengthening primer from a spray bottle.

The voids must be filled with cement mortar, into which in small portions Alabaster is added to speed up setting. After the solution has dried, the sealing areas are rubbed into common plane walls using an abrasive mesh. The gaps between the window sill and the slope must be sealed; this is the main path for cold air to enter. If you subsequently plan to finish the slope with plastic panels, sealing the cracks does not need to be leveled; in this case, sealing can be carried out using polyurethane foam.

If the trim was done correctly along a single line without gaps, you need to complete the finishing on the slopes, paint them, and then fill the gaps with white acrylic sealant. If the edge of the hem is uneven, the sealant is pumped deep into the gap, not reaching the surface by 5-7 mm. The remaining gap is sealed with finishing putty.

How to prevent condensation from forming

A typical consequence of installation errors is the formation of condensation. It can appear both on the windowsill itself and on the glass. Each case has its own reason.

Hypothermia of the window sill occurs due to a violation of the foam seam in the lower zone. The best thing to do in this case is to disassemble the ebb from the outside and scrape out the remaining foam from under the frame. After cleaning, the bottom seam is filled with foam again.

Condensation on glass appears mainly when using single-chamber double-glazed windows with high thermal conductivity. Such windows require a continuous thermal curtain from radiators during the cold season. If the window sill protrudes too much, it will block the flow of hot air and the glass will not warm up properly. The problem can be solved by inserting 2-3 convection sleeves into the window sill, which are also used for pulling cables through the walls of cabinet furniture.

Often when conducting overhaul The old windows in the room have to be replaced. However, window installation cannot be considered complete without exterior finishing, We will talk about how they install and stand) in this material.

Common installation methods

There are several solutions that allow you to find the answer to the question of how to install a window sill with your own hands:

The structure can be fixed using an adhesive composition. This is enough old way, which is extremely rarely used by craftsmen today due to the emergence of more reliable options.
One of the most simple solutions- use of self-tapping screws. The fasteners are screwed into pre-prepared holes in the window sill. The use of special pads and polyurethane foam makes it possible to add rigidity to the structure.
The next method involves using spring metal brackets as fasteners. The latter are screwed to the window sill profile using the same self-tapping screws.
And finally, the last method is to compact the space under the window sill with pads until the edges of the plane enter under the window frame, achieving an increased level of density.

Tools and materials

How to install plastic window sill with your own hands in the most basic way? To do this you may need the following tools:

building level;
screwdriver;
gun for laying polyurethane foam;
perforator;
jigsaw;
pencil;
roulette.

Preparatory activities

First of all, you should prepare the above tools, which will definitely come in handy during the work process. Next, you need to take the correct measurements. The aesthetic appearance directly depends on this installed window sill and its reliability.

When taking measurements, it is important to take into account not only the parameters of the installed canvas, but also whole list additional characteristics. The location of the existing radiator deserves special attention here. If the latter is installed high enough, the presence of a free space of a few centimeters to the lower edge of the window sill can lead to disruption of air circulation in the room and deterioration of the microclimate.

When taking measurements, it should be taken into account that the length of the window sill should be greater than the space of the window opening. The width of the product can be chosen arbitrarily, depending on personal convenience and needs. Convenient option there will be a window sill that protrudes from the wall at a distance not exceeding 8-10 cm.

Window sill trimming

So, let's look further at how to properly install a window sill. Sometimes during installation it is necessary to trim the product so that it matches the parameters of the window opening. The largest window sills reach a length of 3 m or more. The width of the structure can be from 25 to 70 cm.

If the window sill is too large, excess material can be cut off from the side where it attaches to the wall. Special attention Here it is worth paying attention to the cutting line. It must pass without touching the stiffening ribs, which are located inside the window sill. Thus, the structure does not deform during operation and will be securely connected to the frame.

To trim the window sill, it is recommended to use electric jigsaw. It is allowed to use a small hacksaw for wood or plastic, depending on the material of the structure. The work should be done slowly, which will avoid chips and scratches on the front surface of the window sill.

When sawing products, do not forget about safety. Since broken pieces of material can get into your eyes, it is recommended that you wear assembly glasses. To protect your hands, you should use gloves or work gloves.

How to install a plastic window sill: basic steps

Installation of plastic window sills is quite simple:

First, the surfaces are thoroughly cleaned. Pollution is eliminated and garbage is removed.
Having used it, you must determine the horizontal position of the structure and set the beacons. Typically, when installing window sills, their plane is tilted down by about 5 mm. This solution allows the formed condensate to drain from the plane.
How to install window sills on plastic windows? The structure sits on a special glue or building mixture. As alternative solution You can resort to fixing the plane with screws on mechanical supports.
At the next stage, the free space between the concrete slab and the window sill is filled with foam. Excesses protruding outwards are carefully removed using a stationery knife.
Finally, special plugs are installed on the end edges. The surface of the window sill is removed from the protective film.

How to install window sills on plastic windows correctly? To do this, there should be a free distance of approximately 6-7 cm between the heating radiator and the lower edge of the product plane. Only in this case warm air will rise freely from the battery, drying the double-glazed windows and slopes.

How to install a wooden window sill?

Installation is much more difficult. Before you start working, you should pay attention to the quality of the source material. The window sill board should not contain obvious flaws in the form of chips, knots, or other defects. Moreover, you should use a well-dried board. Otherwise, the latter may crack during operation under the influence of sudden temperature changes and changes in humidity levels.

How to install a window sill in this case:

The existing base is planed on all sides, after which teardrops are created on its back surface. The latter are small gutters 5-6 mm deep and 7-8 mm wide.
A felt lining impregnated with antiseptics is placed on the back surface of the board.
The prepared window sill is inserted into the openings in the wall. The teardroppers are installed on pre-prepared wooden blocks. Structural elements are fastened with nails.
The edges of the structure are strengthened with gypsum mortar.

Craftsmen who are well versed in how to install a wooden window sill recommend making a fairly impressive slope into the room, which should be about 20 mm. This avoids the accumulation of condensation on the surface of the product and prevents rotting of the material.

Installation of slopes

Upon completion of the installation of the window sill, slopes should be made. First of all, you need to resort to aligning the window opening vertically and horizontally. The easiest way to cope with the task is to use polyurethane foam. The latter will serve as good protection for slopes from freezing.

Surfaces can be reinforced with mounting mesh or plasterboard. The main task is to maximize the alignment of the planes, as well as the formation of a smooth texture. The top of the slopes can be coated with paint, choosing the color based on the features of the interior solutions.

If the edge of the window sill protrudes into the room by 10 cm or more in relation to the edge of the wall, it is recommended to strengthen the structure. For these purposes, it is worth resorting to using metal corners. But even when implementing such a solution, you should not overload the edges of the window sill during operation, as this may cause deformation of the plane.

Particular attention should be paid to the conditions for installing the window sill on the balcony. In order for the surfaces to “grab” firmly, it is advisable to maintain the air temperature in the range from +16 to +20 o C for several days.

When installing a window sill, it is recommended to apply a lot of polyurethane foam at the ends and in the middle part of the product. To strengthen the structure, it is allowed to use silicone sealants and glue.

Eventually

As you can see, installing a window sill with your own hands is a completely doable task. The main thing is to approach the work carefully and not miss moments that may negatively affect the subsequent operation of the structure.

The attractiveness of the external design of the window opening depends on the installation of window sills. Failure to install them will not only make the room look unkempt, but will also create some inconvenience. In particular, the homeowner will have to regularly eliminate condensation leaks formed on the windows. Otherwise, annual finishing and renewal of surfaces will be required.

There is a job that is simply impossible to handle alone, but installing a window sill on a plastic window with your own hands is within the power of anyone.

To install something, you first need to select and buy this item. If you are just planning to buy a window sill, then it is worth studying the varieties of this element. That's what we'll do now, but installing window sills on windows with our own hands will have to wait for now.

Which window sill to choose?

The window sill has a practical and decorative function. These two parameters are equally important, so you need to carefully select the window sill, taking into account its functional and practical features, appearance and ability long time keep it in its original form.

Polyvinyl chloride or plastic, simply put, is often chosen to create not only window profiles, but also window sills. The structure is empty inside, but has ribs that are responsible for the rigidity of the window sill. This option is affordable, durable, and resistant to moisture. Savings are inappropriate here; you need to choose a high-quality window sill. Otherwise, after about six months, the structure will acquire a yellow tint, become covered with cracks, or change its shape. We will tell you how to install window sills and slopes on windows in great detail.
Plastic with acrylic base attracts the user's attention with its high strength. You will have to pay a lot for such a “fat” advantage. Another advantage is immunity to high temperatures, which the previous option cannot boast of. Acrylic has a glossy surface and can be available in any color.
Wood is even now a popular material chosen for creating window sills. An affordable and even the most successful option is pine. The choice of expensive species will be appropriate only in the case of a special profile that displays the pattern of a special wood. How to install a window sill if there is already a window made of wood will be described below. You need to immediately prepare yourself for the complexity of this process.
Chipboard and MDF with a laminated surface cost much less than the previous option, although in terms of appearance and functionality they are not inferior to natural material. Chipboard is more affordable MDF, but does not tolerate high humidity conditions.
Natural stone is very expensive, but such a high price is not justified by its performance characteristics. It will be difficult to install a window sill to plastic windows with your own hands; its operation must be careful, and you also need to remember the critical points. If you really want to install a window sill made of stone, then you need to choose an artificial option. By appearance it is indistinguishable from natural material, less prone to external damage and is highly durable.

This is all the theory you should know. When the window sill is delivered, you can move on to the essence, and we are ready to tell you how to install the window sill on the windows.

Installing window sills on windows with your own hands is not a difficult job, but it requires compliance with mandatory rules. Only in this case can a positive result be achieved.

When installing a new window, the window sill is not always removed. In this case, you will need to free up space yourself. new design, otherwise, learning how to install a window sill and slopes on windows is pointless. If this is not your situation, then you can safely move on to next stage, and for now we’ll start dismantling the window sill, which has already served its purpose.

This work can be done different ways, which are determined by the material of the window sill.

The wooden structure is removed with a hacksaw and a pry bar, which can be replaced with a crowbar. The window sill must be cut into pieces, otherwise serious damage to the slopes can be caused. Initially, the middle part is removed, after which the side elements will remain. They are firmly connected to the slopes, which complicates dismantling. It is necessary to carefully knock the side parts of the window sill out of their position. The blows must be applied to the end. The use of an angle grinder is unacceptable in the case of a wooden structure; serious injuries can occur. Only after understanding this warning can you continue to learn how to install a plastic window: slopes and window sill.
Stone or reinforced concrete is cut using a grinder. Need special diamond blade to create through cuts. After this, the slab is broken using a sledgehammer or large hammer. Strikes must be struck from bottom to top. The remaining elements are removed using a pry bar.
The plastic window sill has the weakest and simplest fastening. There is no need to rush to dismantle the structure. First you need to remove the ebb, which acts as a kind of external window sill. This will allow you to examine the outside for the presence of fasteners with inside which needs to be unscrewed. If there are no fasteners, simply remove the foam with a knife and dismantle the window sill, rocking it.

When the issue with the old window sill is resolved, you can move on to the next stage. To find out how to install a window sill on windows, you need to prepare the surface for work, which is what we will do now.

Whether you completed the previous step or skipped it, in any case you need to carry out preparatory work at work. And only after that you can learn further how to install a window sill on a plastic window. The essence of preparation is to clean the surface of various debris. Serious indentations also need to be repaired.

How to install a wooden window sill on plastic windows and plastic construction - different processes. Naturally, we will have to consider these two options.

It is necessary to make side grooves in the wall; this is required by the instructions. Their depth should be within 5-7 cm. When you have to install window sills on all the windows in the house, these centimeters in total can amount to a whole window sill, which leads to additional expenses. This subtlety should be taken into account when taking measurements and calculating the total amount of materials. As a last resort, you can reduce the depth of the grooves to 2-3 cm.

The grooves must be even, which means you need to use a level. The measurement is performed as follows:

the square is applied to the frame;
a line is drawn in the horizontal direction from the top line of the groove to the outer cut on the slope.

This will create the top line for the future groove. Deep cuts are made along the marked lines and excess material is knocked out. The window sill should not end directly at the cut of the wall. The structure should protrude 5-7 cm beyond this boundary.

This completes the side grooves, and the slab itself can be left alone and learn further how to properly install the window sill on plastic windows.

There are two ways to carry out the work of installing a window sill. The difference between them lies in fixing the window sill to the window frame, which is done at the beginning. All further stages are carried out according to a single scheme, regardless of the chosen method. How to seal a window sill after installing plastic windows will also be described below.

The fixation process does not involve any difficulties. In the area where the boundary area of the window sill meets the window frame, we make through holes every 30 cm. We press the window sill tightly and screw self-tapping screws into the holes made from the outside. They should go into the slab at least 3 cm, preferably more.

If the fixation described above is not possible, then the window sill is placed tightly under the frame. At this point, you can squeeze out the polyurethane foam in thin strips.

We lay the slab and look at its position. It won’t be perfect right away, so we align it as follows:

We tilt the window sill slightly towards the room, which will allow water to drain from it and not accumulate in the joints. 5 mm will be enough.
Wedges are placed under the slab every 30 cm. Each piece of wood will be cut individually until the desired result is achieved.
The position of the plate must be constantly checked with a level. The result must be perfect, otherwise you will have to do it periodically minor repairs in the form of covering cracks.

If the slab is not fixed to the frame, then polyurethane foam is used. The surface on which the foam will be applied must be moistened with water, which will provide better adhesion. The window sill is installed in its place, and foam is blown under it. Here you need to feel in moderation. Excess foam will still find a way out.

An object weighing up to 20 kg must be placed on the windowsill. In this case, the foam will not be able to swell and squeeze out the slab in the middle part. The stove will remain in a depressed position for at least 10 hours.

All that remains is to restore the beauty (cut off the foam and apply putty to the slopes) and be proud of yourself. We told you how to install a window sill on plastic windows, also made of plastic. Remained unnoticed wooden structure, the installation of which needs to be carried out a little differently.

Some stages will coincide with those that have already been described, so we will not describe them in detail. The work is divided into the following stages.

We mark the slab and arrange grooves in the wall. There are no differences in these processes.
It is better to fix wooden window sills on the window frame, which can be replaced by the base profile underneath. Performed similarly to the above description.
From the end side, a damper tape is glued to the window sill. Thus, the difference between the performance of plastic and wood (thermal and moisture expansion) will be compensated.
Leveling the slab is again done using wedges.
Any wooden window sill has an impressive weight, so foam is not suitable for its installation. Better to use gypsum mortar or cement with sand, which is applied to the wedges.
Place the slab on top and press until it rests against the wedges.
We remove the remaining mortar and apply putty to the slopes.

We told you how to properly install a window sill on plastic windows if it is made of wood. This method can be modified a little to protect yourself. The essence of the modification is to drive a long nail into the wedges. The nail should go right through and protrude a centimeter from above. Anchors are used to secure the wedges. In this case, the window sill rests on nails that stick out from the wedges. This method is more reliable, but requires utmost attention and careful checking of all parameters.

You know how a window sill is installed on plastic windows and nothing stands in the way of putting your knowledge into practice. Moreover, you even know how to repair the void under the window sill after installing the window. In addition to foam, insulation can be laid.

How to properly install a window sill on plastic windows with your own hands: video

Replacing old windows with plastic structures provides for the installation of a mandatory element - a window sill, which is a rectangular or figured board and can be made from different materials: PVC, natural stone, marble, wood, etc. Sometimes it is necessary to change only this part without affecting the window structure, and as an option it can be wooden window sills for plastic windows. Self-execution This type of work requires certain knowledge of how to properly install a window sill on plastic windows. This will help to avoid serious installation errors, which will result in a violation of aesthetic parameters and a reduction in the service life of the window sill.

Preparatory stage and features of material selection

On preparatory stage Measurements are taken of the site on which the window sill will be mounted on a plastic window, joining with the stand profile. The workpiece is cut according to the obtained dimensions:

The length is measured by the width of the window opening - this is the distance between opposite slopes. To the resulting dimensions, 7-9 cm is added for an allowance, of which 5-7 cm is allocated to the extreme protrusion, and 2 cm to the groove under the window structure.
Panel width is measured from profile to external corner slope These dimensions depend on the thickness of the wall and vary from 20 to 50 cm, adding only 5 cm to the protrusion on both sides.

Example of window block sizes

Advice! It is unreasonable to increase the width of the board, as it will block the heating radiator, which can lead to disruption of the circulation air flow and lead to freezing of the glass and the formation of unwanted condensation.

The workpiece is cut according to the dimensions obtained. Models of window sills for plastic windows made of PVC panels, due to their availability, aesthetics and ease of installation, occupy a leading position and are popular among consumers. The technical characteristics of plastic panels have a number of undeniable advantages compared to other analogues: the products are presented in a wide variety of shades. Parts made from PVC panels are cut with a grinder, resulting in smooth edges that do not require additional processing.

PVC panels are most often used to make window sills

Remember! When using a jigsaw or a regular handsaw, be especially careful while working, otherwise the edge will end up with torn nicks and chips, which will be difficult to cover with plastic end caps.

A wooden window sill differs from its PVC counterparts in its increased strength and durability. There are different types of material on the market, which allows consumers to make right choice in accordance with the requirements for such products:

Inexpensive wood - larch, chestnut, pine. Such parts belong to the budget option, so they are mainly installed in country houses and dachas.
Precious wood species - oak and beech - are suitable for any window designs. High-quality wooden window sills for plastic windows look harmonious with a white profile or match other colors of the window frame. Noble wood has an amazing texture, high strength and long service life. The main disadvantage of oak and beech elements is the high price, which is compensated by quality and durability.

Read also: Manufacturing and correct installation wooden window sill

The use of expensive types of wood allows us to produce very durable window sill panels

After the choice of material is finally made, it remains to find out about all the features of the implementation installation work: how to replace an old window sill with a new one, is it possible to install it on a balcony (loggia).

Installation stages

Regardless of what material the window sill is installed on a plastic window, the installation process is carried out using identical technology. Main feature This method is simple and lacks special skills. How to install a plastic window sill correctly or how to install a wooden one? The choice of material is directly influenced by the strength indicator, since this indicator is different for PVC and wood products. Achieve high strength and reliability of wooden and plastic window sills can be determined during the installation process. Correct and competent installation Installing a window sill with your own hands will prevent its subsequent sagging and deformation.

Structure of a plastic window structure

Installation of different types of window sills on plastic windows

You should understand in more detail how to install window sills on plastic windows, and help with this step-by-step description works:

The first and mandatory step is to thoroughly clean the working surface on which the workpiece will be mounted, from construction waste and dust.
The surface on which the window sill will be installed must be clear of debris
For execution further actions You will need a building level to help determine how level the surface is. If there are irregularities, the workpiece is aligned using wedges and beacons. In order to install a wooden or plastic window sill, special glue or mortar is used, which is laid out on the work surface immediately after preparation. The board is placed on fresh mortar and pressed down firmly. In order to secure a large-width window sill, mechanical supports are used - brackets screwed with screws. The number of elements securing the board depends on its length and the strength of the material.
In order for the workpiece to be installed correctly, recesses (grooves) to the thickness of the panel are made in the lower part of the slopes on both sides along the entire length. Marks are made on the slopes, and rectangles are cut out on the workpiece from the left and from the right side. Work on creating grooves is carried out using a hammer drill, grinder and chisel. The depth of the recesses depends on the material from which the slopes are finished - it can be a layer of plaster, putty or drywall. Advice! After installation, cracks and holes are carefully sealed with an appropriate composition, which makes it possible to achieve solidity between the surface of the window sill and the finishing of the slope.
Free space under plastic panel blown in with polyurethane foam. The foaming mixture increases in volume and can move the workpiece placed in place, so a load is placed on its surface. These could be bottles filled with water, bricks, blocks, even books. The frozen excess foam is carefully cut off with a sharp construction knife.
The space under the window sill is foamed
Protective film after installation of the window sill it is removed
On final stage The ends of the plastic window sill are closed with plugs, adding completeness and aesthetics. The protective film is removed from the surface of the panel.

Important! Window sills on a plastic window should be fixed horizontally, it is better to take measurements building level or a square.

The principle of insulating the window sill of a plastic window

If you decide to change the window sill, then you should immediately start insulating it. This will help avoid serious consequences: the appearance of defects, cracks, leading to the formation of drafts and heat loss. Before insulating the window sill of a plastic window, you need to make the right choice of heat-insulating material. Polyurethane foam, which does not require much time to apply, will serve as effective insulation. Also for finishing small cracks and window sill cracks, a special silicone-based sealant can be used on a plastic window.

Features of installation on a balcony

Replacing the window sill of a plastic window on a loggia and balcony depends on whether the room is heated or not. In the absence of heating, it is preferable to choose plastic analogues, as well as blanks made of teak or larch. But even for a warm room, installed wooden blanks require careful treatment with moisture-resistant impregnating compounds.

The wooden window sill panel must be treated with a moisture-resistant compound

You can get a perfectly flat window sill if its fastening is carried out simultaneously with the insulation of the fence (parapet). Thermal insulation boards insert between interior decoration and be sure to leave an air gap, thereby preventing rapid heat loss.

You also need to know how to install a window sill on a balcony for a plastic window. For fastening elements, a base is required, to which bars will be mounted along the entire length of the window sill in increments of 50-60 cm. How many there will be depends on the parameters of the parapet. In order for the finish to look neat, the bars should not extend beyond the base. To fix them, you will need a cement mortar.

Advice! Be sure to attach the workpiece at an angle of 3° towards the room, this will prevent condensation from accumulating on the surface of the window sill. It is possible to make such a slope using planed wooden wedges.

If you are installing a wide and heavy board, then you should know how to ensure that it is securely fastened. Installation should be carried out using brackets for self-tapping screws with a press washer. Long fasteners will not work - best option 4.2x16. The step between the brackets is 20-30 cm, but it can be larger, as it depends on the weight of the installation panel.

A waterproofing tape is attached to the brackets along the entire length, so that moisture from the street will not penetrate into the room. After which the window sill plate is inserted between the window frame and the profile and pressed until it stops. The connection between the loose edge of the board and the brackets is also done using self-tapping screws.

Considering that the installation of window sills on loggias and balconies is carried out in a variety of ways, preference should be given to the optimal and necessary option. Knowing how to replace a window sill, you can do the work yourself without the help of a specialist.

Plastic windows in last years have become an integral element of any interior. Regardless of the style of the room, it is equipped with energy-efficient plastic windows and window sills made of the same material. It is durable and thanks to large assortment decorative films, and very beautiful material firmly entered into our lives. This article will discuss how to properly attach a plastic window sill.

Advantages of a plastic window sill

The most popular materials for window sills are wood, plastic and stone.

Wooden window sills are too finicky and require constant maintenance. In addition, over time they dry out or become damaged from frequent staining.
Stone window sills are certainly durable and beautiful, but they are very expensive and you cannot install them yourself.
Plastic window sills are not just durable, light and beautiful, in their own way technical specifications they match best with windows from pvc profile, which will make caring for them easier.

In addition, the service life will be the same, so after installing the window, slopes and window sills, you will not have to replace or restore any one element.
If the window frame is laminated, then the same film is selected for the window sill.
Due to its properties, plastic is resistant to moisture, so even with possible condensation on the windows it will not begin to rot. At regular care, mold does not form on it, since the surface does not have microcracks.
Lower price than a wooden or stone window sill of the same size.
Resistant to aggressive chemical environments.
Due to the light weight and plasticity of the material, it is easy to cut and install independently without special tools.
A plastic window sill is not a cast slab. It consists of transverse chambers. This not only reduces weight, but also serves as additional thermal insulation.
More expensive models pvc window sill have a special coating that makes it resistant to high temperatures and mechanical damage.

They have only one drawback - low strength.

How are plastic window sills made?

There is no official classification of plastic window sills, but they are conventionally divided into several types.

Standard plastic window sills. They are the most popular. They are made in white, width from 20 to 100 cm in increments of 5 cm. They have the lowest resistance to mechanical damage.

Thermo- and impact-resistant plastic window sills. It is rational to mount them in wide openings that serve as a working surface. For example, when kitchen window sill used as a table. Lamination with a special film gives the product particular strength.
Laminated window sills. They are more beautiful, but their characteristics remain the same. Films not only add color to the window sill, but can also imitate natural materials (stone, wood). Despite the fact that the lamination method is reliable, a number of manufacturers offer window sills that have an acrylic layer on top of the lamination. In this case, the surface strength increases several times (however, so does the cost and weight, which negates its advantages).
The panels are made by extruding PVC blanks with an extruder. The surface is laminated with a film, which makes the window sill smooth and further protects its surface from damage. The thickness of the window sill varies from 1.8 to 2.2 cm.

How to choose a plastic window sill

At first glance, all the window sills are the same and there is a desire to buy the cheapest one. But professionals know several nuances that will help you choose the best quality product.

A plastic window sill must be made from high-quality raw materials that have passed a quality test for safety for humans. This can only be tracked by the product certificate.
The store must also provide detailed specifications material. These include resistance to UV rays (especially important for colored products), mechanical strength and resistance to condensation.

Having received all the necessary information, choose a model that is suitable in design and size.

It is best to choose a window sill white. This is due to the fact that it is guaranteed not to fade under the influence of direct sun rays. And small scratches on it will be almost invisible, unlike colored models.

Advice: cheap plastic may turn yellow after a few years, so it is recommended to choose white window sills from the middle price segment.

A plastic window sill, regardless of price and manufacturer, is a panel containing 1.5 - 3 mm thick stiffening ribs and air chambers between them. It is the number of stiffeners that is responsible for the strength of the window sill. The higher their number, the more load it can withstand.
Panel have standard length 600 cm. You can buy and cut them yourself, or order them ready-made according to individual sizes.

Advice: in order not to make mistakes in preliminary calculations, it is recommended to call a surveyor.

The width of the panels ranges from 20 to 100 cm. Initially, the increase in increments is 5 cm, after 60 cm - 10 cm. Based on this, they measure inner size window opening (depth). Since the window sill should protrude forward (but not completely cover the radiator), add another 10 cm.
For example, the depth of the window sill in a panel house is 15 cm, add another 10, and you get 25 cm - the required panel width.

Preparing walls before installing a plastic window sill

Before installing plastic window sills with your own hands, you need to prepare the walls.

First, remove all debris from the window opening and remove dust from it so that the polyurethane foam has the best adhesion in the future. This is especially important if the installation is to replace an old wooden window sill.
The side walls of the window opening are called slopes. Often the window sill is laid simply from edge to edge, but this is wrong. The secret to installing a window sill is to bury it on the sides into the wall by 2-4 cm. To do this, recesses are made with a hammer drill.

What is needed to install a PVC window sill

If work is carried out in wooden house, then the number of tools required is minimal, in concrete and brick houses everything is more complicated.

Hammer;
Bulgarian;
level 1 m long;
polyurethane foam and a gun for it;
stationery knife;
wedges (made of MDF, laminate or wood).

How to install a window sill on a plastic window with your own hands

Important: the window sill should not cover the battery. Impaired air circulation will lead to the formation of condensation on the windows.

Having the exact dimensions, the window sill is cut with a grinder to the required parameters, taking into account protrusions along the walls of 2-4 cm on each side. If the window opening has a complex configuration, first cut out a model on cardboard and do a fitting. If everything fits, then the outline is transferred to the panel.
If the house is not new, and the opening is much lower than the groove under the frame of the plastic window, which is provided for the window sill, first, wood is placed to the required height. Then the prepared window sill is inserted into the groove between the window profile and the foam to a depth of 2 cm.
After this, using a level, they begin to regulate its evenness. You can make it higher or lower using thin wooden wedges, which either raise or lower the window sill to the desired height. They are placed at a distance of 30-40 cm from each other. In the future, they will remain inside the structure and will play the role of retaining elements.

Tip: you need to install the window sill with a slight slope towards the room, literally 5 mm. This will allow the condensation to roll off rather than remain against the frame.

Then you need to foam the space under the window sill. It is best to use two-part foam that does not expand. When using a regular one, you will have to fill the surface of the window sill with heavy loads. To do this, put heavy bags with construction mixtures, large jars of water, etc.
After 24 hours, the load can be removed and excess foam can be cut off with a utility knife.
As a final step, decorative plugs are placed on the sides of the window sills.

The places where the window sill adjoins the internal slopes of plastic windows are covered with corners.

How a window sill is attached to a plastic window photo

Tips for installing a plastic window sill with your own hands

The process of polymerization (hardening) of polyurethane foam occurs much faster in a humid environment. Therefore, before filling the space under the window sill with foam, it is moistened with a spray bottle or any other sprayer.
It is not recommended to pour too much foam. Since it has the ability to expand several times and can push the window sill upward, despite the load. To avoid this, small gaps are left between the freshly extruded strips of foam, which are guaranteed to close when expanded.
If it is not possible to fit the window sill panel into the slopes and under the window profile, then it is adjusted perfectly precisely. All joints are treated with colorless silicone sealant.

DIY installation of a plastic window sill video