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Replacing the window replacement or installing a new one with your hands is the most critical moment in establishing any type of window. The fact that it is designed to play not only an aesthetic role in the interior but also a protective one - window companies near me.

It is constantly influenced by all kinds double pane windows cost of temperature differences and mechanical stress. It is he who suffers from constant exposure to moisture and sunlight.

And all these things largely determine the peculiarities of its installation. Materials for window sills can be very different - wood, PVC, marble, etc. And, of course, all the nuances of the building will to some extent, depend on them.

However, for this action, there is still a general list of recommendations that allow you to navigate the work's algorithm.

It is effortless to install a plastic window sill. Any special skills and abilities are not required here. It is essential only the accuracy in the process of sawing PVC, when should do without intense pressures, to the place of sawing did not appear scratches and chips.

This article will discuss how to install the plastic window sill. First, however, we immediately note that the window sill must be installed before installing the window sill because otherwise, there may be a reasonably decent gap at the junction.

Width and length of a plastic window sill

Of course, at the initial stage of installation of the plastic window sill is necessary to cut a blank of this very window sill of the required length and width for us.

A bolt cutter best performs the cutting process because, with its help, you can achieve perfectly smooth edges. Still, in the absence of this tool, you can use an electric jigsaw, but it is necessary to see it carefully, without pressing it on the plastic or rubbing against it, because this can leave traces.

Without a jigsaw, you can see off the workpiece, and an ordinary saw. Do not worry about nicks in the place of cutting, and the plastic end caps will cover them on the window sill.

So, first of all, let's determine how long the window sill should be. To do this, measure the width of the window opening with a tape measure and add at least 60 mm to the obtained value.

Otherwise, the profile of the plastic corner used to install window sills will stick out of the window sill, which is inadmissible.

We will determine its width by cutting the window sill to the calculated length. The width of the plastic window sill is determined as simply.

It is necessary to consider that the allowable window sill protrusion from the opening is within 50-70 mm; otherwise, it will overlap the radiator and impede the passage of heat, which can cause misting and the formation of ice on the windows.

However, under a window sill is brought in about 20 mm; these figures need to be added to the depth of the window opening, measured from the profile to the wall.

Using the received values, we adjust our workpiece under the demanded width (depth). But that's not all; as you may have noticed, our workpiece is not included in the opening; it is necessary to cut the parts that hinder her in this case.

This should consider that it is better to make it so that the protruding right and left parts of the window sill are recessed into the wall.

To do this, you will have to make small recesses in the wall with a punch, but after installing the window sill and puttying these recesses, it will be possible to achieve a monolithic effect of the window sill and the wall.

Thus, having attached the window sill to the opening, we make marks for cuts, taking into account the above, and cut out the rectangles that interfere with our installation on the left and right. Now our billet plastic window sill is ready to be installed in place.

A general list of recommendations

Window sills are usually installed along with PVC windows simultaneously as the sills and other structural elements.

However, there are cases where separate installation of these elements is necessary.

For example, when replaced due to mechanical damage, when repairing and dramatically changing the interior.

Or just in a new building developer left the installation of window sills and soffits at the discretion of the buyer:

  • The window sill is attached to the inside of the room and at the bottom of the window opening;

  • At the bottom of the window sill, at most 60 mm from its edge, there is a gutter - a tear duct up to 20 mm deep, which is necessary for the drainage of water;

  • The final stage of installation comes only after the preparation of the bottom plugs;

  • The lower part of the mortar of the side slopes is cut down to the wall.

  • Then the wall is cleaned from debris, dust, dirt, etc.

The window sill is laid like this:

  1. So that the board is in a strictly horizontal position (measured with a level), and the cross slope of the window sill inward from the window frame is approximately 30;

  2. The wedges, the basis for installation, must not extend beyond the wall.

  3. Therefore, if properly installed, they will require additional fixation with plaster.

  4. After that, proceed to the removal of the window sill, wetting the wall with water and covering it with lime-gypsum mortar so that the level of the mortar exceeded the story of the wedges by 15 mm;

  5. The window sill is put into the mortar and pressed with force onto the wedges until it stops; The last step is to level out the excess mortar and encourage it to flush to the wall plaster with subsequent grouting.

  6. The window sill enters the groove made on the joist at the bottom of the frame.

  7. As for the side slopes located in the lower part, the same actions are performed - grouting and subsequent grouting.

However, we often have to deal with plastic and wooden window sills, the installation of which strength and reliability can be achieved for each option.

Correctly install the window sill. To exclude its subsequent sagging and breaking, you can place metal strips under it and enter the latter's ends in the bottom stub.

  1. First, the cleaning is carried out;

  2. Then, using the horizon level, set the window sill utilizing screeds.

  3. By the way, when installing the window sill, it is tilted down by 5mm, so that the moisture accumulated by condensation is not retained and flows down;

  4. The free space is filled with installation foam, the excess of which is then carefully cut off with a construction knife;

  5. In conclusion, the window sill ends are protected with stoppers, and the window sill is removed from the protective film.

  6. Such window sill is fixed with a special mortar or glue, but you can also use screws on mechanical supports.

  7. For the same that the warm air was free to rise from the radiator up, drying thereby the inside of the window sill and glazing during the heating of the room, window sill installation from PVC requires leaving a 60mm protrusion.

  8. The length of the plastic window sill must not exceed the width of the window opening at 15 - 20 cm.

  9. Inside the room, the ledge of the window sill must be at least 5 - 7 cm in width.

  10. Installing this type of window sill over the radiator of steam heating, as a rule, leave a small gap.

How to fix a plastic window sill

Here we come to the main question that bothers us - how to fix a plastic window sill.

Even though unique clips allow you to mount the window sill directly to the plastic window, we recommend using wooden bars - wedges for this purpose.

The reason for this is the excellent endurance of the window sill to the loads in this case. And so, how to install the plastic window sill correctly:

  1. It is necessary to put the pre-cut piece in place, putting a part of it under the window profile by about 20 mm.

  2. In the next step, wooden wedges are hammered under the window sill to press it tightly against the window frame. Before fixing the window sill, it is necessary to use a construction level to precisely align the plastic window sill in all directions.

  3. Adjustment is made by changing the size of wooden wedges.

  4. Next, you must fill in the gap under the window sill with installation foam, and it will get rid of drafts and reliably fix the window sill.

  5. However, it is best to use a special two-component foam, which does not expand as it dries.

  6. In the case of conventional foam, it is necessary to load the entire surface of the plastic window sill sufficiently so that it will not bend under the action of the foam.

  7. After the foam dries, it is cut off, and the plastic window sill end caps are installed. The installation of the plastic window sill is considered complete.

Install a plastic window sill with your hands - from measuring to installation.

Installing the window sill is usually the final stage of establishing a plastic window.

It is usually carried out by professionals - the company where you ordered the window.

However, window sill installation is relatively simple compared to the window's structure, and you can do it yourself.

We will consider installing a window sill made of plastic since this material is quite popular - cheap, durable, not prone to corrosion, and easy to clean.

So, we will need the following tools: a jigsaw or circular saw; a level; a gun for the foam and the foam itself (if there is no gun, you can do without it); a tape measure and a pencil or marker; a hole punch with a chisel (if you have to trench notches for the window sill).

Of course, any work on installing anything begins with careful measurements. First, determine what width your window sill will be - it depends on the thickness of the load-bearing walls and how much it will protrude beyond the wall.

The recommended protrusion - is a maximum of 10-15 centimeters; otherwise, it will just get in the way. To the total width of the window sill, you need to add 2 centimeters since this part will be under the window.

Add 5 centimeters to the length of the window sill on each side - this part will go into the side so that the cut edges of the window sill will not be visible.

If there are no soffits, it is necessary to punch out grooves 5 cm deep. Measured and checked all the calculations - you can cut off the excess from the window sill, which you should have already purchased.

Of course, you should buy if you already know the dimensions, and you will have to cut only the length, and certainly not the width. You can see plastic with an electric jigsaw and a manual circular saw - whatever you have in the household. At the worst, take a hand saw for metal.

Before you begin the installation, clean the area under the window and install small pads of wood. Why this is done - the window sill should have a slight slope to the outside of the window - so that the moisture from watering flowers or condensation does not accumulate on it and flow outward.

To set the desired slope, you need to install wooden wedges and put the window sill on them.

Then, using a level, you need to align the plane along the length to prevent warping and set the desired slope in width by adjusting the pads.

The slope is recommended at 1 cm; no more is necessary. By the way, the sale of special adjustable pads, but if you have not bought them or did not consider it essential to do this, no problem - to adjust the slope can simply change the height of the wedges, putting them under the narrow slivers, for example.

Then all this will be filled with assembly foam, and the strength is not worth worrying about. So, after adjusting the slope and aligning the plane of the window sill, we insert its ends into the grooves on the slopes, once again check the correct position, and begin to fill with foam.

Using foam with a low expansion coefficient avoids lifting the window sill.

The ideal would be to use a gun for foam - professional foam almost does not expand, so it will be enough to put on the window sill weight of 10-15 pounds, so it will not lift.

Fill all the gaps carefully - the strength of the installation depends on this. On this work is almost finished, put the load and wait 24 hours for complete hardening.

The technology of installation is the following sequence of works:

  • First, you need to determine the exact dimensions of the panel. The distance between the soffits is added by 6-7 cm to go into the wall. The soffits pick the width; usually, the window sill on the balcony is flush with them.

  • According to the dimensions, the desired part is cut. For cutting, an electric jigsaw or circular saw is used. If there is no power tool, you can use a metal hacksaw.

  • It is also necessary to hollow out slots in the side slopes so that the edges of the window sill go into them. On the balcony is correct to do it with a hole punch.

  • Having hollowed out such grooves, all the debris is carefully removed with a broom, producing priming of the surface is desirable. This will ensure a more reliable adhesion of the installation foam.

  • To align the window sill on the balcony on the level, under it are installed wooden or plastic bars, which provide a tight fit to the bottom edge of the window.

  • Such supports are installed every 10-15 cm.

  • After that, the place of installation is moistened with a sprayer, and the window sill is installed in its class and once again checked with a level.

  • Completes the installation of window sills on the balcony blowing all the gaps and voids. You should take a foam with a low expansion coefficient for this operation. After caulking the cracks, the window sill should be loaded. For example, put a few cans of water on it or a few bricks.

Advantages and disadvantages of PVC window sills

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

Plastic products are popular because they have many advantages before finishing elements made of other materials. The benefits of plastic window sills include:

  • attractive appearance;

  • easy cleaning from dust and dirt;

  • long service life;

  • high strength due to the presence of reinforcing ribs;

  • harmless 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, preventing moisture penetration into the room and, consequently, the appearance of mold in the house.

Disadvantages of plastic window sills also exist, but they are very few. For example, PVC slabs are subject to scratches in the case of careless use. On them also you can not put hot objects - this can lead to deformation of the surface and the loss of the beautiful appearance of the finishing element.

Installation methods

Installing the window sill with the help of wooden pads requires a lot of time, 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 utilizing a particular compound. Nowadays, this method is used very rarely, as there are more convenient and reliable.

  • The fastest installation of the window sill is carried out with the help of self-tapping screws. First, holes are drilled in the window frame, into which the hardware is screwed. The junction is treated with acrylic sealant, and then the edge of the window sill is placed under the glass and fixed with screws. To maximize the rigidity of the board, special pads are put under it, and the place is blown out with assembly foam.

  • The following method involves the installation of PVC window sills with the help of spring clips. These fasteners are screwed to the substage profile of the product with self-tapping screws. After that, the board is mounted in the groove formed between the window frame and the bracket, and the product is installed.

  • Do not use fasteners (self-tapping screws and staples) in the last variant of installing plastic window sills. This is the most time-consuming method but also the most reliable. Its meaning is that the wedges are driven under the board until their edge is pressed against the frame as tightly as possible.

Each method has its pros and cons. For example, installing the window sill utilizing self-tapping screws near the opening sash is undesirable. Options for installing PVC window sills differ only in the way the product is fixed under the frame. The remaining stages of work here are identical.

What is needed

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 depends to a greater extent on the class of devices used.

So, good tools and work are more manageable, and their service life is long, especially when you consider that the devices are likely to be needed in the future, as window sills are often installed under each window of the house or apartment.

So, for work, you may need the following materials and tools:

  • PVC window sill;

  • Electric jigsaw, angle grinder;

  • Cylinder of foam and a particular gun;

  • Construction level, measuring tape, pencil;

  • Self-tapping screws or staples (depending on the chosen method of window sill installation);

  • wooden wedges (thin boards and the like);

  • chisel and hammer;

  • office knife;

  • trowel and primer.

The product should not protrude more than 8 cm.

To qualitatively install any window sill, you must first make measurements. This moment is crucial because the appearance and durability of future construction depend on it.

Here, in addition to the properties and characteristics of the polyvinyl chloride product, many additional parameters should also be considered. For example, there must be a certain distance between the radiator and the window sill.

Otherwise, air circulation will be disturbed, leading to a deterioration of the microclimate in the room.

When measuring, it is worth remembering that the length of the installed plate should be slightly longer than the distance between the side sills. The product is entered into slots made deep in 2-3 cm.

As a rule, the window sill is mounted over the radiator, so the value of the front protrusion of the plate should be no more than 8 cm. If this figure is more, the PVC plate will not allow the hot air to rise from the radiator to the window. And this will lead to the formation of moisture.

The vertical distance between the radiator and the window sill should be more than 10 cm.

Because the product is installed directly under the window, modern models are equipped with a unique profile with the possibility of fixing the sill.

The measurements cut the window sill blank of the required width and length. Performing the sawing of PVC products with a bolt cutter is desirable.

Using this electric tool will allow you to achieve perfectly smooth edges. In the absence of a turbine, you can use an electric jigsaw.

Less often, the trimming of PVC window sills is carried out with a plastic hacksaw. But it is necessary to see with her very carefully.

Do not put too much pressure on the saw, as this can lead to the appearance of chips and cracks on the product.

When working with plastic, it is necessary to remember safety measures. It is a somewhat fragile material, so small particles can fly out when you cut it intensively. Wear safety glasses and work gloves.

Preparing the window opening

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

Immediately before installing the window sill, it is necessary to prepare the place of its installation. Make grooves in the side soffits with a chisel and hammer at this stage. After that, the home of installation of the product is cleaned from debris and primed.

Next, special spacers or wedges are attached to the window frame. They can be fixed with plaster mortar. Finally, spacers are used to install the board at the correct level and with the required inclination.

In this case, consider that the slab should be at an angle of 1-2 degrees to the side of the room. This way, water from watering plants or condensation will run off, not collect under the slab.

After you put the window sill in, check how tight and flat it is. Then, if necessary, trim the edges of the product.

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

Necessary: If you find gaps in the window opening, seal them with installation foam.

Mounting and Installation Instructions

To blow the assembly foam, use a particular gun

As noted earlier, fixing the product can be done in several ways. We will consider the latter - with the use of wooden spacers and installation foam, as it is the most reliable and very popular in recent times among people doing repairs with their own hands. The procedure is as follows:

  1. Insert the window sill in the prepared place. When doing this, use the building level and wooden screeds, located at a spacing of not more than 80 cm.

  2. At the front end, under the slab, set the supporting wooden stakes. The distance between them is no more than 50 cm. The supporting elements must not go beyond the plane of the wall. The distance from the chocks to the side slopes is 10 cm.

  3. Re-check the angle of the window sill with a level. If it does not match the previously indicated value, adjust the pads in thickness.

  4. Blow the hole between the slab and the concrete surface with assembly foam. But not completely, but only to fix the product.

  5. We evenly place a load on the slab. This will not allow the foam to raise the window sill. Here it is important not to overload the design, as its surface can deform. Often as a load, use 3-4 tanks of water with a volume of 5 liters.

  6. Blow out all the free space under the window sill with assembly foam. Use a particular gun so that the sealant doesn't splash on the sides and doesn't get on your clothes.

  7. After that, leave the window sill alone for 2-3 days to allow the foam to cure fully. Cut off the excess of the binder with a box cutter.

  8. If you later find gaps under the board, treat them with acrylic sealant.

  9. In the final stage, stoppers are installed on the ends of the window sill. To do this, use adhesive for PVC products. In the end, all that remains is to remove the protective film from the product.

Place a few water bottles on the window sill to prevent the foam from lifting the slab.

Necessary: The window sill must fit tightly with the window frame, and the gap between the board and the walls should not exceed 4 mm. "Ears" of the product (the part that protrudes beyond the inner soffits) must also be tightly pressed against the wall.

-Instructions for installing a PVC window sill

Installation of plastic window sills is not an easy job, requiring appropriate knowledge and skills. Installing such products with your own hands, be careful and follow the rules mentioned above because the price of spoiled PVC tile is much higher than its installation cost.

The concept of a window is inextricably linked to the installation of the window sill. Therefore, the window sill is a completing link in the window structure and is also a subject of the interior.

You should think beforehand about what kind of window sill board reach you need - do not forget that too broad a sill may block access of warm air from radiators and break its average circulation.

Think about what will stand on the window sill - flowers, vases, lamps, etc., or you will leave it without all these items. Rules for installing window sills implicate installation technology depending on the window material. However, if you want, you can install a window sill made of wood and stone into a plastic window.

And wooden window sills or reinforced concrete walls with a textured surface will be suitable for wooden windows. Today a great variety of proposals according to your desire and taste. But, first, let's get acquainted with the installation rules of window sills from different materials, their features, and quality indicators.

For all types of window sills, it is necessary to do preparatory work
  • Clean the surface of the base on which the window sill will be installed from dust and debris.

  • Moisten the surface under the window sill to improve the adhesion of the floor with the mortar.

  • Prepare a place for the window sill at the rate that the window sill board went into the groove of the wall at 50-100mm.

Rules for installing window sills made of wood:

  • We prepare a blank window sill based on the size of the window opening, determine its overhang, or, if the walls are perfectly flat, if desired, install the window sill flush with the wall. The thickness of the window sill should vary between 50 - 60 mm.

  • The window sill is exposed utilizing wedges, which must not protrude beyond the plane of the wall. After their leveling, the wedges are fixed with mortar to prevent displacement, and we eventually reach the desired level. If this is a room with high humidity, we use only cement mortar.

  • We prepared a bed for the window sill from the mortar on the level so that the artillery covered the wedges. Install the window sill - it must exactly "move in" on the prepared surface in the side grooves in the wall and be tightly fixed.

  • The joints of the installed window sill around the perimeter with the soffits and the walls must be sealed with acrylic compounds, which do not allow moisture and is easy to paint the desired color. The surface of the window sill board from below is treated with wood preservatives.

  • If you doubt the stability of the installed window sill, you can additionally fix it to the window frame. This is done with the help of self-tapping screws - from the facade, passing the screw through the window frame, and going into the window sill for 50-70 mm.

  • We perform coating of the window sill varnish or other material acceptable to you.

Rules of installation of plastic window sills

These are the most popular window sills because they are installed simultaneously with plastic windows, which are increasingly gaining market windows. And no wonder plastic windows, besides their functionality, have a great design and are convenient.

Installation rules for window sills made of plastic are almost the same as for wooden window sills, but there are nuances. Briefly, in this order, I will outline the main points so as not to repeat them.

  • We make measurements and cut a plastic window sill with the account - the length plus the termination in the walls on both sides of 50mm or more at your discretion.

  • The width is determined - the depth of the slope plus 10 mm, which goes under the window, plus 80mm or more (if you wish) to release the window sill.

  • We put the screeds on the principle of a wooden window sill, the space between the sill board, and the supporting part of the bottom of the foam. Above load - the easiest option is 4-5 three-liter cans of water (as I did) and leave for a day.

  • Install the plugs on the sides.

Similar installation rules for stone, marble, concrete, etc., window sills.

I want to add from personal experience that many people do not wish radiators to protrude beyond the plane of the walls, although it violates the heat exchange in the room and can cause fogging of windows from the inside. Nevertheless, they are sunk into a recess in the wall, and the installed window sill, without support, hangs like a cantilever.

In this case, even before installing the window sill plate, it is necessary to install wooden or metal crosspieces to redistribute the load and support them on the walls along the length of the sill.

According to standards, there is general quality control for all types of window sills.

This is a series of rules for the quality of the work:

  • The upper surface of the window sill must be installed with a 1-1.5% slope to the room's interior.

  • The lower surface of the window sill must be insulated from the masonry walls with antiseptic material.

  • Within one room, all window sill boards must be at the same level.

You have seen that the rules for installing window sills are not that complicated. If you want, you can do everything yourself. Specialists do everything according to a template, always in a hurry, and the blanks are standard. So install the window sill yourself, and let it be a decoration of your interior.

When the new window sill is cut and the bottom of the window with soffits is prepared and cleaned, then you can begin its installation. First, the canvas is placed under the window. For this purpose, modern double-glazed windows are equipped with a unique profile, where the outside is attached to the sill. First, it is necessary to try on the window sill, placing it in a groove under the window at approximately level so that its slices go under the window sill.

Next, it is necessary to align the panel by height. It is convenient to use wooden wedges and bars placed under the window sill (on the edges, in the middle). In this case, it should be achieved that there is no gap between the glass and the panel. To do this, the window sill must be pressed firmly from below. If wedges are used, it is recommended to push them in more profound so that they do not interfere later to putty the wall under the window.

The timbers take all the load acting on the window sill

When the far side of the leaf is fixed, you should align its near edge. There is one requirement: it must be horizontal, and the correctness is checked with a building level.

Next, the window sill must be securely fastened. Then, it is simply blown out with foam. It fills the gap under the plastic panel. It is better to use balloons for the gun; blowing should be careful so that it is evenly filled with all the space after the expansion. After the foam has cured, its excess should be cut off with a construction knife.

To ensure that the pressure did not lift the window sill upwards after expansion, the panel should be evenly put in some weight. It is recommended that the board be covered with something beforehand to avoid damage. It is necessary to put something flat under the load, such as a piece of reps, so that the weight is evenly distributed over the window sill area and does not get dents or humps.

During 1 hour, it is better to periodically check the level of the panel to see if anything has happened. When a warp or a dent appears, you can fix it; for example, you should remove the weight from the hole. You can put a bar, a wedge, a piece of Styrofoam, or other material at hand under the dent. If you get a slight distortion, it is enough to simply move the load, to add/loosen it on some sides.

Removing the weight from the window sill is possible in about 10-12 hours (manufacturers say that the complete hardening is carried out within 6 hours, but it is better to wait a little longer). This time depends on the amount of foam. The more it is blown in, the longer it will harden.

This is how PVC window sill installation is performed. If the window sills are not yet made, they must be made after the installation is complete. When doing so, maintain a right angle between the panel and the slope. Plastic plugs are put on the ends of the window sill, and it is recommended to do this after the walls are finished. Under the panel, over time, sometimes there is a crack; it can be filled.

After finishing, the walls should be glued with painter's tape horizontally under the window with an indent of 2 mm. Next, you need to squeeze acrylic sealant into the corner of the gap, and the excess should be removed with a damp sponge.

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