How to replace a window sill

How to replace a window sill Table of contents:

  • 1 When to replace an old window sill
  • 2 What will it be
  • 3 Workflow
  • 4 Instrument preparation
  • 5 Dismantling the old windowsill
  • 6 Window sill mounting
  • 7 to summarize
  • 8 videos

Most often, window sills are mounted when engaged installation of windows. Therefore, a separate installation of window sills performed extremely rarely, only in special cases. But it happens such that during repair work or redevelopment of the apartment, Improper coverage needs to be replaced (usually more wide window sill). Then you have to dismantle the old windowsill to install a new one. In this article we will consider some reasons window sills are needed from time to time change what material to choose for the future window sill, and how replace the windowsill. If you need to make a replacement windowsill, you, despite the lack of experience, will be able to to do. And now about everything in more detail.

When to replace an old windowsill

The old window sill brokeBroken old windowsill

Nothing lasts forever, we all know this, so from time to time any the thing needs either repair or replacement. There are many reasons. What are the reasons for replacing the windowsill? Here are a few of them:

  1. Damage was formed on the surface of the coating, reducing overall attractiveness of the windowsill. The aesthetic look is lost when the presence of small scratches, cracks, chips and various kinds of deformations, when window sills are made of wood.
  2. There are violations of the integrity of the product – deep chips, large cracks due to which the window sill can collapse in any moment. Often the window sill serves us as an additional shelves where we usually put our flowerpots, seedlings or other things. Therefore, when such deep damage is formed, it replacement is required.
  3. Crumbling of a wall adjacent to a window sill or total destruction the coating itself. Often this leads to the fact that the windowsill can fall at the most inopportune moment. Moreover, quality sealing in this case is significantly deteriorated, which allows cold air from the outside to freely enter premises. This is especially unpleasant in the winter.
  4. The final reason is the reorganization of the entire space and change the overall design of your room, which is old windowsill may not fit. It may be that you just need a bigger windowsill – for various purposes.

TooToo narrow

Whatever the reason, the window sill needs to be changed, even if he’s just tired of you. Is it possible, if desired, to complete all the work for dismantling and installing the windowsill yourself? You will find out the answer Further, familiarizing yourself with the installation technology of the windowsill. But before how to mount it, you should decide what material there will be a future windowsill. Let’s look at some of them.

What will he be

We live in a time of technological progress. Nowadays there are so many materials for construction, and all of them so diverse and universal that our ancestors used us envied. And this applies not only to durability and quality. This is a beautiful, aesthetic look, which is important.

If we talk about window sills, then the market has modern models are presented in various options. Assortment of goods is so great that you can choose a model that would be perfect fit into the interior design, fully performed its functions, had various design features, coped with different kind of load and had a very reasonable price.

Plastic window sillPlastic window sill

Plastic products. They are one of the most sought after materials on the market, as they are available for the majority. Despite the low price, a plastic window sill can be called practical and reliable, resistant to light and heat, able to serve you a long service, since it does not rots. However, with strong mechanical stress, it can to break down. Given the fact that the material is synthetic origin, such a windowsill has a good environmental friendliness, which is very important, especially for those families that have small children. And of course, one of the important advantages of plastic products can be called a wide range of colors and configurations goods, as well as their low weight. This fact allows you to choose the window sill that will be in harmony with the general the interior of your home. It should also be noted that replace such a window sill is possible according to a simplified scheme.

Wooden window sillWooden window sill

Wooden crafts. The tree will be in trend is always. Naturalness always captivates and gives nobility product. This material was used by our distant ancestors, but has remained relevant to our time and does not lose its popularity. Wooden window sills will give a feeling of warmth and comfort in the house, especially since they have a beautiful natural pattern and texture pleasing to the eye. If you are a connoisseur environmentally friendly and natural materials worth giving preference for just such an option. Thanks to modern technology, pre-treatment of raw materials contributes to the fact that finished products during operation will not rot, deform or break. But, of course, all this is necessary pay, and a lot. The price of wood products is much more expensive than from plastic, so not everyone is able to afford them. If you connoisseur of the breed of the highest class, dear will suit you window sills from the whole massif.

There are also low-budget options made from such materials, like MDF and particleboard.


Acrylic products. Very durable and reliable window sills that are gaining popularity thanks to their qualities. Yes, they cost 2-3 times more than products from PVC (plastic), but you pay for good reason. After all, such window sills able to support the weight of not only objects that will be on them installed, but also the weight of the person. Often using such window sills equip a recreation area, expanding the canvas and adding for the comfort of the pillow, here you can sit with a cup of tea, watching happening on the street from the window. They have many advantages: not scratch, not afraid of heavy weight, spilled liquid or fallen cigarettes. They are easy to care for and easy to clean. They do not lose its original appearance, despite the long term operation. And importantly, such products can be any colors and shapes. This is the case when the price is fully consistent quality, and even more.

Of stoneMade of stone

Products from natural and artificial stone. As before, and now, the stone also remains popular material in construction. But such window sills may not fit into the interior of your room. Only when everything is matched correctly marble and granite coatings add solidity and sophistication in the decoration of a house or apartment. Their main the strength is durability and reliability. Still window sills made of stone can not always be called safe, because they have quite a lot of weight and are radioactive.

These are far from all the materials from which they can be made. window sills, but they are the main and most popular. The decision which material to choose is up to you. Based on your funds, goals for which you will serve windowsill, and from interior design. Agree stone a window sill by a plastic window – this is most often inappropriate, more, when there are no stone decor elements in the room. Given all the factors, you can purchase the perfect option. Not worth it save on quality, as this may affect the future.

An important nuance in choosing a suitable design is its parameters and sizes. When choosing a product, please note that its the length should exceed the width of the window by several centimeters (10–20), but the width is chosen based on personal preferences, but only so that he does not close the radiator. Just important not go too far so that the installed window sill does not break in place, where there is no support.

We decided on the windowsill, let’s look at the detailed instructions on how to install it correctly with your own hands.

Work sequence

Measures to replace the windowsillActivities for window sill replacement

To complete the installation of a new windowsill, you will have to implement a full range of activities. As you know, planning leads to success. Therefore, it’s important to prepare everything in advance, get acquainted with the upcoming work and have an idea what you need will do. Let’s look at the work that will be needed perform in several stages:

  • procurement of tools for work;
  • dismantling of an unusable windowsill;
  • installation of a new window sill.

As mentioned earlier, the easiest way to replace plastic products, this applies not only to window sills, but also windows. If they are made of other materials, the sequence of the installation process will be the same, only now you need to pay more attention to accuracy in work. So let’s we will find out what materials you will need in the process.

Tool preparation

Preparing ToolsPrepare instruments

If you want to install a new window sill quickly, quality and without hitches, prepare such instruments:

  • roulette;
  • level;
  • hammer;
  • chisel;
  • hacksaw;
  • scrap;
  • drill or perforator;
  • polyurethane foam;
  • jigsaw;
  • silicone sealant;
  • sandpaper;
  • cement mortar;
  • putty knife;
  • respirator;
  • mounting knife;
  • boards with a small cross section;
  • paint for slopes.

If you don’t have something from this list, do not rush to run to score. When you are not sure that you will need these tools in in the future, you can borrow them from good friends or acquaintances, and even better – with relatives. Having collected all the necessary equipment, You can begin to dismantle the windowsill.

Dismantling the old window sill

Dismantling the windowsillWindow sill dismantling

Actually, removing an old window sill is not as difficult as may seem at first glance. The main thing is to strictly follow leadership. It is also important that when working should be attentive, careful and accurate so as not to damage anything too much. Cracks and chips at the window you do not need. Consider how you can remove window sills of various types.

In order to protect your hands from injuries, use gloves.

If the windowsill is wooden, a hacksaw and a scrap will come to the rescue. For First you need to check how the window sill is attached. When it is attached to the wall, hit several times on the windowsill below hammer to loosen the mount. Crowbar try it lift up. Then just try to get it. Your attempt not successful? Use a chisel and hammer. IN Otherwise, use a hacksaw. Make cuts in different places and take out the pieces with a crowbar. It happens that under wooden window sill is glass wool, which can damage your airways. To avoid personal injury, proceed with work in a respirator.

With a concrete window sill, things are more complicated, since the effort will have to attach more. With such work, dust and garbage, therefore it is important to protect your respiratory organs and eyesight. To remove it, you will need a hammer or grinder. If there are none, you can use a hammer and a chisel, but this significantly reduce speed.

Remove the plastic window sillWe remove the plastic windowsill

It’s easy enough to remove the plastic window sill, as it fastens mainly thanks to polyurethane foam. Dismantle plastic window sill can be two methods. The first is simple, but with great destruction. The essence of the work is to carefully remove slopes and repel plaster. Then it remains to cut the mounting foam with a sharp knife. After that, the plastic window sill is easy to remove. a sharp upward movement and towards yourself. The second option is more gentle, thanks to which you can save plaster and slopes. First file the mounting foam, thanks to which it is fixed windowsill, hacksaw. Similarly, you need to remove the liquid plastic, remaining at the joints of the slopes of the windowsill. When you cut this layer, gently pull the product towards you. If all else fails, again cut the mounting foam under the windowsill and repeat all first.

After the window sill is removed, the surface must be prepared to install a new one. Remove all debris, dust, mortar and polyurethane foam. Now the surface is ready to install a new coverings.

Window sill mounting

It's important to fit well.Important good fit to size

Do not assume that to perform a window sill replacement just take out the old windowsill and insert a new one on it a place. There are some rules for preparing this niche and products. These rules are mandatory, therefore, compliance very important.

Installation scheme for a plastic window sillScheme plastic sill installation

So, to install a new windowsill, you need to follow such a sequence:

  1. To fit the window sill into the window opening as much as possible accurate, you need to cut out the excess parts in the place where it will be installed windowsill, given its size. Also check the groove itself, where the canvas will be installed. Measure all sizes to prepare a new canvas. From how competently executed measurements, depends not only on the overall appearance, but also on the strength the design and functionality of the windowsill. If the old window sill remained intact, it can be used as pattern-template to make a new canvas, if the dimensions of the past the windowsill was fine with you. You can cut a new blade jigsaw or saw. It is important that the cutting does not form defects and cracks, so do not rest strongly on windowsill.
  2. When installing a window sill made of wood, all cut out edges from the ends need to be treated with an antiseptic to Protect the material from mold and reduce moisture permeability.
  3. Prepare the opening itself on which the window sill will be installed. If the height of the purchased window sill is less than the old, a horizontal base must be cement screed. If the windowsill is thicker, the niche needs to be deepened.
  4. If in the course of work gaps and cracks have formed in the walls, which are adjacent to the installation site, they need to be repaired. For this use ordinary putty or cement mortar.
  5. Application of sealantSealant Application In Place where the window sill will be adjacent to the frame, the entire width of the window the opening must be applied with silicone sealant. So you You can achieve tightness and eliminate the formation of voids, which contribute to the penetration of cold inside your home or apartments.
  6. In the opening you need to put the prepared boards. They will serve support for the new windowsill and take on the main load.
  7. Using a level, check the horizontalness of the entire structure. Deficiencies need to be corrected by doing everything perfectly smoothly.
  8. Now set the window sill plate to the prepared boards.
  9. LevelLevel Check Again use the level to make sure installation.
  10. Place a load on the windowsill. It can be books, a heavy box, water bottles or something that will be under by hand.
  11. Take the mounting foam and blow it all side and back strobes. If a plastic construction is installed, some manufacturers add special profiles to the kit, thanks to which the installation process of a new windowsill will become easier.
  12. FoamingFoaming Edge under the windowsill, which protrudes, it is necessary to close up with cement mortar or foam, to fix it.
  13. Now take a technical break, a day long, to foam or the solution is completely frozen.
  14. If the gaps were treated with cement mortar, the surface should be sanded with a grater or fine sandpaper.
  15. Now it remains only to protect the ends of the windowsill with a cap and remove the protective coating from the canvas.
  16. To give the window a natural and aesthetic appearance, a slope is necessary plaster or paint.


It should also be noted that the window sill should not interfere heat from the radiator rise up and spread across apartment, so the ledge is recommended to do from 6 to 8 cm. Now your windowsill is ready!

To summarize

You could make sure to replace the windowsill with your own hands. perhaps. This procedure is simple and does not require professional skills, you can do everything in 2 days, taking into account the break for drying. Replacing one window sill, you can easily make this with other windows. Moreover, due to independent installation, you can save money on hiring workers.


To increase the life of the new blade during installation necessary:

  • choose the right width and length of the future window sill;
  • correctly measure and cut the canvas;
  • use quality supplies;
  • comply with all installation rules;
  • be accurate and careful when performing work;
  • After installation, regularly care for the surface.

We hope that our tips will help you competently and quickly. replace the old windowsill. If you succeeded, write to us at comments, it will inspire not only us, but also those who will read this article!


Watch the following video, here are a lot of useful tips. for dismantling and installing a plastic window sill:

In this video, the dismantling of plastic windowsill:

Read also:

  • How to install a wooden window sill.
  • How to install a plastic window sill.

Like this post? Please share to your friends:
Leave a Reply

;-) :| :x :twisted: :smile: :shock: :sad: :roll: :razz: :oops: :o :mrgreen: :lol: :idea: :grin: :evil: :cry: :cool: :arrow: :???: :?: :!: