How to properly install a window sill on plastic windows with your own hands: step by step instructions, video. Installing a plastic pvc window sill with your own hands video tutorial How to install a plastic window sill

23.06.2020

When replacing old window structures, you must immediately install new window sills from modern materials. Today at the top of the popularity of plastic products. The width of the PVC panel is 60 cm, which makes it possible to install them with almost any wall thickness. How to install a plastic window sill qualitatively and reliably, read on.

Preparatory work
Exception - installation of wooden structures

Preparatory work

The preparatory stage includes the measurement and selection of the design, the selection of tools, the purchase of building materials. If the double-glazed windows have not been replaced, the old window sill will need to be dismantled. When replacing a window, the old window structure is completely removed. Installation of a new double-glazed window is carried out by the manufacturer's specialists. Installation plastic window sill can be carried out also by specialists or independently by the customer.

Installation of a plastic window sill is carried out only after installing the window frame and double-glazed window.

When replacing only the panel, you must first make the correct measurement:

Measure the width of the window opening. Throw another 10 cm and get the total length of the structure.
The width of the panel is equal to the distance from the installed window to the corner of the wall plus 5 cm per ledge. It is not advisable to make the base of the window wider, since air circulation is disturbed, which leads to fogging of the glasses.

Tools and materials

To install a plastic window sill with your own hands, you will need a set of tools:

carpenter level;
electric jigsaw or grinder;
carpentry knife and hacksaw;
ax and hammer;
square;
marker and masking tape.

From the materials should be prepared:

sealant;
gun and mounting foam;
window sill panel;
three sets of plastic or wood substrates of different widths;
two end caps.

Preparing the installation site for the PVC window sill

With a hacksaw, electric jigsaw, axes remove the old structure and window frame. The cement screed is removed along the edges of the wooden product. The opening is cleaned of broken building material, insulation.

Specialists install a new PVC window so that a distance of at least 5 cm is maintained between the base of the window opening and the lower part of the frame. The left opening will serve as a support for the new structure.

If you plan to install a PVC window sill with your own hands longer than the window opening, grooves are sampled on the sides at the base. To do this, you need a hammer and grinder. First, they cut the wall, and then gently knock it out with a hammer construction material. The height of the groove is such that the new panel fits easily. The length of one groove is more than 5 cm.

The distance between the base of the window opening and the frame is foamed mounting foam or put in insulation. After the foam has completely solidified, the excess is cut off with a carpenter's knife. When installing a plastic panel the size of a window opening, mark the attachment points of the brackets at a distance of no more than 80 cm.

Before installation PVC products it is necessary to once again clean the base from debris and dust. Be sure to wet the brick with water to ensure adhesion.

Installing a plastic window sill

All materials are purchased and tools are ready to go. Start installing the window sill.

Determine the width of the structure. It can be the same as the width of the old base. When replacing windows and installing a new PVC product, its new width is calculated. Ideally, the edge of the panel is in the same plane as the middle of the battery heating system. When mounting the panel, the edge of which protrudes beyond the battery, vent holes are equipped in the panel itself. Such holes are also made in the casing in front of the battery. They are needed for good air ventilation in front of the window, which protects the window structure from condensation.
Select the length of the plastic base. When two windows are located side by side, one holistic design is preferred. When installing PVC window sills in size equal to the window opening, the length of the panel is made shorter by 10 mm.

According to the selected panel sizes, they make an order at a hardware store. Shop masters immediately carry out trimming according to the specified parameters. Sometimes they buy a blank, and trimming is done at home on their own.

The support for mounting plastic window sills is made from substrates purchased in advance. The width of the bar must be at least 50 mm, and the length must not exceed the width of the product. The shortest underlay should be 100mm less than the width of the panel. Particular attention is paid to the thickness of the substrate. After installing the bar, the panel should enter the window sill space between the lower window frame and the substrate.
Before installing the substrate bars, the surface of the base is leveled with cement mortar. At least three substrates are required per design. The optimal distance between the bars is 40–50 cm.
The supports are aligned strictly horizontally and the correct installation is checked using a level in all planes. Make a control installation of the plastic panel. The result of the correct fastening of the substrate is a tight entry of the structure into the gap between the edge of the window and the support.
Do-it-yourself installation of plastic window sills begins with the removal of the protective film from the side adjacent to the window. Install plugs on the ends of the panel. Carefully insert the structure onto the fixed supports.
The panel is firmly in place. Align the product with light tapping in relation to the window frame. Carry out a control measurement of the level in two directions.
Left and right leave gaps of 5 mm, which makes it possible to protect the panel from deformation. At the end of the installation, the gaps are sealed with sealant.
Carefully foam the space under the plastic window sill with mounting foam. If the panel is poorly fixed, it will skew from the increase in foam in volume.
Spacers are installed along the edges and in the center of the window opening. They are made independently or bought transforming spacers in the store. They do not allow the mounting foam to lift the installed base of the window opening. When the foam hardens well, the spacers are dismantled and the excess foam is cut off.
After the slopes are installed, they begin to seal the gaps. Masking tape is glued along the edges. Fill the gap with silicone sealant. Remove excess and remove masking tape.
The protective film is removed after completion of work.

Exception - installation of wooden window sills

Window sills made of oak, pine, beech, ash or cherry wood make the interior of the house warmer and more comfortable. giving preference natural materials, many owners of apartments and houses instead of artificial plastic choose natural wooden bases. The stores sell wooden panels covered with varnishes of different shades with different surface textures. Having made your choice, proceed to install a wooden window sill with your own hands.

Wall preparation

The base is cleaned of dust and litter. The surface is moistened with water to ensure good adhesion. If there is a niche under the window, metal or wooden poles so that the panel does not hang in the air. The wooden structure in this case is dressed in a metal frame.

Window sill alignment

Pre-expose the window sill with wedges, achieving its slope into the room by only 2 degrees. Along the window, the board is located strictly horizontally. When all the necessary indicators are achieved, the wedges are strengthened with a small amount of mortar by removing the workpiece.

Fixing a wooden window sill

A layer of mortar is laid on the base, covering the wedges by 5 mm. Mainly used cement mortar, but you can apply putty or gypsum. Install the window sill in place and firmly press it against the wedges until it stops. The excess that comes out is removed with a spatula.

Advice! For safety net, an insulating film is first laid on top of the solution to protect the tree from direct contact with the aqueous solution.

Sealing and reinforcement

For more reliable fixation from the side of the facade, long self-tapping screws are driven into the end of the wooden window sill through the window frame. After the fastening of the structure is completed, small cracks are sealed with liquid acrylic.

The final stage in the arrangement of window openings is the installation of PVC window sills with your own hands - with proper preparation and minimal repair skills, this work can be done independently, quickly and reliably.

Characteristics of PVC window sills

The window sill is the most visible part of the window design and the most functional part of the entire window. They prevent heat leakage from the room and are a barrier to outside cold air, they serve as a support for various interior items (including very weighty and bulky ones - for example, flower pots). Do-it-yourself installation of a PVC window sill will allow you to acquire a strong, durable and beautiful surface along the entire length of the window, thanks to the following qualities of these products:

Resistant to sunlight, high and low temperatures and humidity;
Resistance to impacts, scratches, pressure and other types of mechanical impact;
Lightness - compared with wooden product similar dimensions, the weight of a plastic window sill is 3-5 times less. This greatly facilitates installation work, from preparation to installation;
Ease of sanitization and resistance to chemically active substances;
Durability - both in terms of maintaining aesthetic merits and strength qualities;
Environmentally friendly, no harmful fumes and emissions during the entire service life.

The service life of plastic window sills is from 10 to 30 years - that is, it is quite comparable with the service life of a newly installed plastic window. To achieve such longevity, the installation of PVC window sills with your own hands must be based on the observance of a number of rules and recommendations.

Installing a PVC window sill with your own hands - according to GOST we are preparing a window opening

The width of plastic window sills varies from 30 to 70 cm. The greater the width, the greater the mass of the product and the more stringent the requirements for the base for mounting.. Of great importance is the type of opening to be equipped - whether the window sill is installed together with a plastic window or partial installation is performed. The design advantages of PVC boards make it possible to mount them under old wooden frames - such budget repair will allow you to update window openings at a relatively low cost.

Any preparation for installation work with PVC window sills begins with the removal of their "predecessors" and the study of the exposed wall. You should be prepared for the fact that the result of our study will be deplorable. In houses old building under the massive wooden window sills, you can find jagged walls with mortar influxes, shaped dips and potholes. It will not be possible to manage with the removal of construction debris; the basis for PVC window sills must be even and solid.

You will have to work with the solution, since the volume of filling activities will be small. It is necessary to take a flat board 10-30 cm longer than the length of the window opening and use a level to fix it to the wall. The upper edge of the board will become the lower boundary of our "foundation". Further, in the side walls, cuts are made under the window sill to be installed - 5-10 cm from the corners. At the third stage, all the cracks in the depth of the opening are isolated - between already installed window and opening. After that, the base for the window sill is poured with cement or cement-crushed stone mortar.

Modern cement mixtures harden quickly, but the proper strength is reached in 1-2 days. The installation of PVC window sills should be started no earlier than the specified period, otherwise the base can be damaged during the installation process - and then you can not even dream about the accuracy of the work.

How to install a PVC window sill - installation instructions

With a solid and even base, installing a PVC plate as a window sill will not take much time, but care and accuracy should be exercised. First of all, you should decide on the size of the "removal" of the end relative to the wall - it is recommended to limit it to 8 centimeters. With a larger offset, it is difficult to guarantee the strength of the structure under strong pressure on the end part.

However, if under the window it is planned to install heating batteries in special niches, the dimensions of the “removal” can significantly exceed 8 cm and reach 15 or even 20 cm. In this case, a deep insertion of the entire slab into the side walls and additional fasteners along the window line is necessary. The battery itself should be located with a large margin relative to the window sill extended above it, for good air circulation in the heated room. There are a lot of advantages, they are quite feasible and made of plastic.

Modern models of plastic windows are equipped with a hidden rail profile at the bottom of the end. It is to this rail that the window sill plate is attached, which guarantees the tightness of the entire window. Even if there is no rail groove, it is forbidden to move the plastic window sill further than the vertical border of the window - it is not intended for contact with atmospheric precipitation and frosty air.

Do-it-yourself trimming of plates when installing PVC window sills is carried out using ordinary hacksaws for metal and exactly at the installation site. Further installation goes as follows:

The plastic plate is pre-inserted in its place to assess the accuracy and horizontalness of its location. Pay attention to tight contact with the lower edge of the window frame, as a guarantee of the future tightness of the entire structure;
Wedging is in progress - wooden wedges should be installed between the base and the window sill to firmly fix the PVC window sill. A window with a width of 1.5 meters will require 3 wedges (at the edges and in the center), for large windows, 4 or 5 wedges are required;
The window sill is removed and the wooden wedges are attached to the mounting base (lightly at first, they can be adjusted). Be sure to remove the wedges from the outer end, because. a separate rail will be fixed under the front border of the window sill;
The PVC board is mounted on fixed wedges and checked for levelness with a level. If necessary, the position of the wedges is changed or they are simply cut on the spot.
When the whole structure is located precisely and firmly, an even rail is attached to the front of the opening - it will serve as an additional and reliable basis with an effort on the end part of the window sill;
Once again, the strict horizontalness of the plate installed on wedges and rails, its tight contact with the window frame, and resistance to mechanical pressure in various places are checked. It will not be superfluous to check the free opening and closing of window sashes;
Before finally fixing the PVC window sill, all internal openings between the wedges and the rail are treated with mounting foam. The PVC plate gently slides into place - when it hardens, the foam will expand and fill the entire internal space.

It remains to fix the window sill in the mounting gaps on the side walls, and this must be done with the help of fragments of stones or bricks, in combination with a cement-sand mortar. After the mortar and foam harden (that is, the next day), you can proceed to the design of window slopes, the installation of heating radiators and other stages of repair and improvement of the premises.

Replacing old windows with plastic structures involves the installation of an obligatory element - a window sill, which is a rectangular or figured board and can be made of different material: 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. Do it yourself this type of work requires certain knowledge on how to properly install the window sill on plastic windows. This will help to avoid serious installation errors, which will be followed by a violation of aesthetic indicators and a decrease in the service life of the window sill.

The preparatory stage and features of the choice of material

On the preparatory stage measurements are made of the site on which the window sill will be mounted on plastic window, docking with the base profile. The workpiece is cut in accordance with the obtained dimensions:

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

Window block size example

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

The blank is cut according to the obtained dimensions. Models of window sills on a plastic window made of PVC panels, due to their availability, aesthetics and ease of installation, occupy a leading position and are popular with consumers. Specifications plastic panels in comparison with other analogues have a number of undeniable advantages: products are presented in a wide variety of shades. Details from PVC panels are cut by a grinder, as a result of which the edges are smooth, not requiring additional processing.

PVC panels are most often used for the manufacture of window sills.

Remember! Using a jigsaw or conventional hand saw, be especially careful during work, otherwise the edge will turn out with torn notches and chips, which will be difficult to block with plastic end caps.

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

Inexpensive wood - larch, chestnut, pine. Such details are budget option, so they are mostly installed in country houses and at cottages.
Noble breeds of wood - an oak and a beech are suitable for any window designs. High-quality wooden window sills for plastic windows look harmoniously with a white profile or are matched to 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 more than offset by quality and durability.

Read also: Production and proper installation of a window sill made of wood

The use of expensive wood species allows the production of 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 steps

Regardless of the material from which the window sill is installed to the plastic window, the installation process is carried out using an identical technology. Main Feature this method is simplicity and lack of special skills. How to install a plastic window sill 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. It is possible to achieve high strength and reliability of a wooden and plastic window sill during the installation process. correct and competent installation do-it-yourself window sill will exclude its subsequent deflection and deformation.

The structure of the 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 action is a thorough cleaning of the work surface on which the workpiece will be attached from construction debris and dust.
The surface on which the window sill will be installed must be free of debris.
For further steps, you will need building level, which helps determine how flat the surface is. If there are irregularities, the workpiece is set using wedges and beacons. In order to install a wooden or plastic window sill, special glue or building mixture, which immediately after cooking is laid out on the work surface. The board is installed on a fresh solution and strongly pressed down. In order to fix the window sill of a large width, mechanical supports are used - brackets screwed on with screws. The number of elements that fasten the board depends on its length and the strength of the material.
In order for the workpiece to be installed correctly, recesses (strobes) are made in the lower part of the slopes on both sides for the entire length of the panel thickness. Marks are made on the slopes, and rectangles are cut out on the workpiece from the left and from right side. Work on the creation of strobes is carried out using a perforator, 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! Slots and holes after installation are carefully sealed with an appropriate composition, which allows achieving solidity between the surface of the window sill and the slope finish.
free space under plastic panel blown with mounting foam. The foaming mixture increases in volume and can move the workpiece put into place, so a load is placed on its surface. It can 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 windowsill is foamed
The protective film is removed after installation of the window sill
At the final stage, the ends of the plastic window sill are closed with plugs that give completeness and aesthetics. The protective film is removed from the surface of the panel.

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

The principle of insulation of the window sill of a plastic window

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

Features of installation on the balcony

Replacing the plastic window sill on the loggia and balcony depends on whether the room is heated or not. In the absence of heating, it is preferable to give the choice to plastic counterparts, as well as teak or larch blanks. 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 composition

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

You also need to know how to put a window sill on the balcony for a plastic window. For fastening elements, a base is needed, 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. To finishing looked neat, the bars should not go beyond the base. To fix them, cement mortar is required.

Advice! Be sure to attach the workpiece at an angle of 3 ° towards the room, this will allow condensate not to accumulate on the surface of the window sill. It is possible to make such a slope with planed wooden wedges.

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

A waterproofing tape is attached to the brackets along the entire length, due to which moisture from the street will not penetrate into the room. After that, the window sill is inserted between the window frame and the profile and pressed against the stop. The connection of the loose edge of the board with the brackets is also carried out using self-tapping screws.

Considering that the installation of window sills on the loggia and balcony is carried out by the most different ways, you should give preference to the optimal and desired option. Knowing how to replace the window sill, you can do the work yourself without the help of a specialist.

If the house has windows, then there must be window sills. Qualitatively installed window sill performs not only a decorative function - it serves as a protection against the penetration of cold into the room.

Structures can be wood, granite or PVC. Do-it-yourself installation of a PVC window sill can be carried out only after studying the installation technology of PVC products.

Why PVC window sills
Preparing the installation site
General recommendations

Why PVC window sills

Unlike wooden window sills, PVC products perfectly resist sudden changes in temperature.
High impact and scratch resistance.
Does not require anti-corrosion coating.
The presence of chambers provides good thermal insulation qualities.
Installation of the window sill can be carried out independently.
Easy care during operation.
PVC perfectly resists prolonged exposure to moisture.
Possibility of installation both for plastic, and for wooden designs of windows.

Selection of tools and material

High-quality installation of a plastic window sill with your own hands can only be carried out with right choice source material, tools and exact implementation of recommendations for installation.

During installation you will need:

Polyvinyl chloride window sill and plugs on its ends.
Corner, building level, marker and tape measure.
Silicone sealant and polyurethane foam.
Electric jigsaw, puncher and screwdriver.
cement mortar.
Stationery knife and clean rags.

Preparing the installation site

A new PVC window sill will look good if you carefully prepare the place for its installation. This is especially important when replacing old windows. After dismantling the outdated window opening, the presence of chips and cracks around the window is checked. If necessary, the masonry should be restored. Remove small debris and dust, and apply a primer to the base.

Important! Before installing a PVC window sill, check the quality of the window frame installation to avoid cold penetration into the house.

When the new window is installed and the base for mounting the PVC window sill is carefully prepared, you can start measuring the space and preparing the window sill for installation. Before installing a plastic window sill, it will have to be cut to the width and length of the opening.

The width of the window sill can be the same as the slopes or a little more. In length, it is necessary to cut the product 4-6 cm more than the distance between the slopes. In the vertical slopes, two horizontal cuts are made, into which the window sill will be inserted.

Plastic window sills can be installed in three ways:

Mounting foam or special glue is used to fix the product.
The window sill is fixed with brackets.
To install a PVC window sill, a profile is used.

Instructions for working with glue

Step #1. On the side slopes of the window opening, cut two notches at the same level, and clean the window sill well and, if necessary, deepen.

Step #2. Before installing a new window sill, dry and coat the surfaces with a primer.

Step #3. Insert the window sill cut to size into the grooves under the window frame.

Step number 4. Wedged the window sill between the frame and the window opening with wooden wedges. Insert wedges in the middle and edges of the window sill.

Important! There should be no gaps between the window sill and the window frame.

Step number 5. Between the window sill and the window opening, install linings so that the surface of the structure is horizontal.

Step number 6. Pump mounting foam with a small coefficient of expansion between the PVC window sill and the window opening. To prevent the window sill from rising, lay a load on top of it.

Step number 7. Install plugs on the side cuts.

Important! A window sill that strongly protrudes beyond the wall must be strengthened by applying cement mortar.

Step number 8. Remove the load 12 hours after foaming the window sill.

Rigid installation instructions

Such installation of a PVC window sill is considered the most durable and durable.

Step #1. Make the marking and trimming of the window sill, as in the previous installation option.

Step #2. On a previously cleaned window opening, perform cement screed. Adjust the height of the screed so that the new window sill fits exactly into the grooves of the window frame.

Step #3. To fix the product, use liquid plastic or silicone glue.

Instructions for working with brackets

Step #1. A support profile is installed under the window and securely fastened. At least 4 brackets are mounted in it with self-tapping screws. The maximum distance between the brackets is 25 cm. Fastening is best done with self-tapping screws with press washers.

Step #2. The PVC window sill is being installed on the brackets. You should hear a click when properly seated.

Step #3. The window sill is connected to the frame with screws.

Step number 4. Wide window sill additionally fixed to the cement mortar.

Instructions for working with a metal profile

Step #1. In a horizontal position, attach to the window sill metallic profile L or U-shaped.

Step #2. Install the cut window sill into the groove and secure with self-tapping screws.

Step #3. Free space between new design and blow out the base with foam.

Step number 4. Additionally, the structure can be strengthened with a cement mortar.

While working with a perforator, protect your hands with gloves and your eyes with special glasses.
Mounting foam adheres much better to a wetted surface. Before foaming, moisten the surface of the base and the back of the window sill with a spray bottle.
Sealant is best pumped in strips, leaving space between them.
The protrusion of the window sill beyond the window slope line should not be more than 60 mm, and the length should exceed the width of the window opening by a maximum of 15 cm.
If the window sill must be strictly horizontal along the length, then it is necessary to make a slight slope from the window along the width. The slope should not exceed 3%.
During the installation of window sills, it is necessary to take into account the location of the heating devices so as not to worsen the microclimate of the room.
The rigidity of the PVC window sill increases significantly when using a wooden backing. All bars must be the same size. The length of the bar is equal to the distance from the window frame to the edge of the opening. The distance between the fixed planks is 25 cm.
After complete hardening of the foam, its excess is removed. The wall under the windowsill is puttied and the decorating begins.

After reading the article to the end, you learned how to properly install a PVC window sill in several ways. Each mounting method has its advantages and disadvantages. With the right approach and high-quality performance, installing a new window sill is not as difficult as it seems at first glance.

Watch another video about installing a window sill. The owner of the apartment shares his installation experience.

Many people want to have modern metal-plastic windows in their house, and many have already installed them a long time ago. But in addition to installing a double-glazed window, you need to take care of finishing the opening. It is decorated with wood, stone, or simply plastered on a concrete surface. The most correct option is to cover the opening with plastic and install a PVC window sill. We will tell you what advantages PVC finishing elements have, consider how to install plastic window sills and give detailed instructions by installation.

Advantages and disadvantages of PVC window sills

PVC window sills are very popular due to their durability and moisture resistance.

The popularity of plastic products is due to the fact that they have a lot of advantages over finishing elements made from other materials. The advantages of plastic window sills include:

attractive appearance;
ease of cleaning from dust and dirt;
long service life;
high strength, due to the presence of stiffeners;
harmlessness to health (PVC window sills are made from environmentally friendly and non-toxic materials);
high moisture resistance.

In addition, when fixing the product, mounting foam is used, which prevents the penetration of dampness into the room and, as a result, the appearance of mold in the house.

Plastic window sills also have disadvantages, but there are very few of them. So, PVC plates are prone to scratches in case of careless operation. Hot objects should also not be placed on them - this can lead to deformation of the surface and loss of beautiful view finishing element.

Installation methods

Installing a window sill with wooden linings is time-consuming, but this method is the most reliable.

There are several methods for installing PVC products. Let's consider each of them.

The first method, the oldest, involves fixing the element with a special composition. Nowadays, this method is used extremely rarely, as more convenient and reliable ones have appeared.
The fastest installation of the window sill is carried out using self-tapping screws. First, holes are drilled in the window frame, into which the hardware is screwed. The junction is treated with acrylic sealant, after which the edge of the window sill is brought under the double-glazed window and fixed with self-tapping screws. To give maximum rigidity to the slab, special linings are placed under it and the resulting place is blown out with mounting foam.
The next method involves the installation of PVC window sills using spring clips. These fasteners are screwed to the substitution profile of the product with self-tapping screws. After that, the plate is mounted in the groove formed between the window frame and the bracket, and the product is installed.
AT last version installation of plastic window sills, no fasteners (self-tapping screws and staples) are used. This is the most time-consuming method, but also the most reliable. Its meaning is that the wedges are driven under the plate until its edge is pressed against the frame as tightly as possible.

Each method has its pros and cons. For example, it is undesirable to install a window sill using self-tapping screws near the opening sash. Installation options for PVC window sills differ only in the way the product is fixed under the frame. The remaining stages of work here are absolutely identical.

What will be required

Before proceeding to the installation, it is necessary to prepare materials and tools. As the first rule of professional builders says, the quality of work largely depends on the class of tools used. So, with good fixtures, it is easier to work, and their service life is longer. Especially when you consider that tools are likely to be needed in the future, since window sills are often installed under each window of a house or apartment. So, for work you may need the following materials and tools:

PVC window sill;
electric jigsaw, grinder;
mounting foam cylinder and a special gun;
building level, measuring tape, pencil;
self-tapping screws or staples (depending on the chosen method of installing the window sill);
wooden wedges (thin boards and the like);
chisel and hammer;
stationery knife;
spatula and primer.

Preparatory work

Taking measurements

The product should protrude no more than 8 cm

To qualitatively install any window sill, you must first take measurements. This moment is extremely important, because both the appearance and the strength of the future structure depend on it. Here, in addition to the properties and characteristics of a PVC product, many additional parameters should also be taken into account. For example, there must be a certain distance between the battery and the window sill. Otherwise, air circulation will be disturbed, which will lead to a deterioration in the microclimate in the room.

When taking measurements, it is worth remembering that the length of the installed plate should be slightly greater than the distance between the side slopes. The fact is that the product is inserted into the grooves made with a depth of 2-3 cm. As a rule, the window sill is mounted above the battery, so the size of the front protrusion of the plate should be no more than 8 cm. If this figure is greater, then the PVC plate will not allow hot air to rise from the radiator to the window. And this will lead to the formation of moisture. As for the vertical distance between the battery and the window sill, it should be more than 10 cm.

Due to the fact that the product is installed directly under the window, modern models equipped with a special profile with the possibility of fastening the ebb.

Trimming the window sill

In addition to a jigsaw, you can use a grinder or a special hacksaw to trim a plastic window sill.

In accordance with the measurements, cut the blank of the window sill of the required width and length. It is advisable to cut PVC products with a grinder. Using this power tool will allow you to achieve perfectly smooth edges. In the absence of a turbine, you can use a jigsaw. Less often, pruning of a PVC window sill is carried out with a hacksaw for plastic. But you need to cut it very carefully.

Do not apply too much pressure to the saw, as this may cause chips and cracks on the product.

When working with plastic, you need to remember the safety measures. This is a rather fragile material, so when it is intensively cut, small particles can fly out. Wear safety goggles and work gloves.

Window opening preparation

To make grooves for the window sill, use a chisel and a hammer

Immediately before installing the window sill, it is necessary to prepare the place of its installation. At this stage, grooves are made in the side slopes with a chisel and a hammer. After that, the installation site of the product is cleaned of debris and primed. Next, special spacers or wedges are attached to the window frame. They can be fixed with a plaster solution. Stands are used to set the slab at the correct level and at the required inclination. At the same time, keep in mind that the plate should be located at an angle of 1-2 degrees towards the room. So water from watering plants or condensate will drain, and not collect under the stove. Then attach the window sill and check how tight and even it becomes. Trim the edges if necessary.

Apply a layer of moisture-resistant primer to the installation site of the window sill

Important: If you find any gaps in the window opening, they must be blown out with mounting foam.

Assembly and installation instructions

Use a special gun to blow the mounting foam

As noted earlier, the fixation of the product can be performed in several ways. We will consider the latter - using wooden spacers and polyurethane foam, as it is the most reliable and very popular lately among people doing DIY repairs. The procedure is as follows:

We insert the window sill into the prepared place. At the same time, we use the building level and wooden beacons, which we have in increments of no more than 80 cm.
At the front end, we install supporting wooden blocks under the slab. The distance between them is no more than 50 cm. In this case, the bearing elements should not go beyond the plane of the wall. The distance from the blocks to the side slopes is 10 cm.
Re-check the angle of inclination of the window sill with a level. If it does not correspond to the previously specified value, then adjust the pads in thickness.
We blow out the hole between the slab and the concrete surface with mounting foam. But not completely, but only to fix the product.
We evenly place the weight on the plate. This will prevent the foam from lifting the sill. It is important here not to overload the structure, as its surface may be deformed. Often, 3-4 tanks of water with a volume of 5 liters are used as cargo.
We blow out all the free space under the windowsill with mounting foam. Use a special gun so that the sealant does not splatter on the sides and does not get on clothes.
After that, we leave the window sill alone for 2-3 days so that the foam completely hardens. Cut off excess binder with a clerical knife.
In case of subsequent detection of cracks under the slab, treat them with acrylic sealant.
At the final stage, plugs are installed on the ends of the window sill. To do this, use glue for PVC products. At the end, it remains only to remove protective film from the product.

Important: The window sill should fit tightly with the window frame, and the gap between the slab and the walls should not exceed 4 mm. The “ears” of the product (the part protruding beyond the internal slopes) should also be pressed tightly against the wall.

Video instruction for installing a PVC window sill

Installation of plastic window sills is not an easy job that requires appropriate knowledge and skills. When installing such products with your own hands, be careful and follow the above rules, because the price of a damaged PVC plate is much higher than the cost of its installation.