Are Interior Window Sills Necessary?

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Whether you are building a home or renovating an existing one, you may be wondering how you can save money. You might even be thinking about the interior window sill. You may look at this, thinking it is purely a decorative object; however, it actually provides a very important function in your home.

Therefore, the answer is, yes, an interior window is still necessary. Whether you are designing new windows or looking to upgrade your existing ones, you need to make sure you maintain the interior window sill. Otherwise, your home is going to experience some significant issues.

As a result, as we take a look at the different options available for interior window sills, it is important to think about what they are, why they are so important, and how you can get as much out of them as possible. What do you need to do if you want to get as much as possible out of your interior window sills?

A Window Sill: What Is This, Really?

A wooden interior window sill
A wooden interior window sill

Before we dive into the details, it is important to take a closer look at what we are talking about when we discuss window sills. It is also called a window bottom or a window ledge. It looks like a shelf, is a flat piece of wood, metal, or plastic, and it is usually located at the base of the window. An interior window sill is critical to the functionality and design of the window itself.

Of course, there are two broad types of window sills available. The first is an interior window sill, which you will see if you look at your window from the inside of the home. In other cases, there may actually be an exterior window sill as well. If you venture to the outside of your home and take a look at the windows, you may spot this.

A basic UPVC plastic window sill
A basic UPVC plastic window sill

Window sills come in a wide variety of sizes and styles. Therefore, you do have some control regarding the appearance of your window sill. You have the ability to customize this to meet your individual needs and expectations.

What Does a Window Sill Do: Exploring the Form and Function

Now that you are familiar with what a window sill is, it is time to take a closer look at what they do. Even though much of what a window sill does is decorative, there are several specific purposes that they serve:

  • For example, window sills are important to the overall structural integrity of your window and frame. Because they are rigid, they prevent the window from flexing, making sure they maintain a strong structure.
  • In addition, a windowsill can also protect your wall, making sure that water leads away from the building. This can prevent rain from getting into your home, avoiding significant damages.
  • Of course, much of what a windowsill is is also decorative. You can place candles, pictures, and plants on the ledge. Therefore, this is a great way to brighten up the inside of your home. Depending on how you use your window sill, you need to think carefully about how wide you want it to be.

Now, it is time to take a closer look at some of these benefits so you understand just why these window accouterments are so important.

1. Keep Out the Water

One of the most important reasons why you need to make sure you have a window sill is that this is important for keeping out the water. You need to make sure you keep water away from the windows and your home. A window sill is important for every construction project because they keep out snow and rain. That way, you can prevent wood rot from developing in your home.

If water creeps into the windowsill, it could significantly damage the drywall. They can cause mold to grow, damage your paint, and lead to massive repair bills. The worst part is that you may not realize you have a structural problem for many years. By the time it is discovered, it is already too late. There is a significant amount of wood rot, and you are looking at a substantial repair bill.

In addition, if you allow mold to grow in the walls of your home, you can cause the people in your home to develop a wide variety of medical problems. In particular, those who suffer from chronic respiratory conditions, such as allergies and asthma, are going to suffer significantly.

Therefore, if you want to keep the moisture out of your home, you need to install window sills. They can go a long way toward keeping your house safe and preventing hefty repair bills later.

2. They Are Required

Windows (with sills!) being added to a new construction home.

Another reason why you need to install a window sill is that they are required. If you hire a contractor to install Windows in your home, they are going to be required to install window sills. Therefore, you are not going to have much of a choice.

If you are installing them yourself, you may think you can avoid these requirements; however, it is still critical for you to follow them. Whether or not you understand the reasoning behind them, anyone you sell the house to is going to expect to see window sills.

If they are not there, you are not going to have anyone who will purchase your home. As a result, it is important to avoid this issue ahead of time and make sure you install window sills.

The good news is that you do have a lot of control regarding the type of windowsill you install. Therefore, you should take a look at your home, think about what you need, and select the best choice for your building. Window sills are required, so you need to treat them as such. Even if you are doing a project on your own, you need to make sure you include them in the blueprint.

3. They Protect the Window

Next, you must make sure you always include a window sill because they protect the window. They are an integral part of the structure of the window itself. In essence, they make up the bottom of the frame. If you do not install a windowsill, the window is going to sway back and forth when the house begins to settle. As a result, the integrity of the window itself is going to be threatened.

If you do not include a windowsill, the window could start to crack when the foundation settles. If you see that the glass in the window starts to spider outward, you will need to replace the entire window. This can be incredibly expensive.

Therefore, think of the windowsill as a brace. It will reinforce the window and the wall itself. When you are trying to budget your project, you need to make sure you include a window sill. Otherwise, you will have the budget to replace all the windows relatively quickly.

If you are interested in learning more about the relationship between a window sill and the structure of your window, you may want to reach out to a contractor who can help you. That way, you can learn more about why you have to include this critical feature when you are putting together a project for your home.

4. They Look Nice

Coffee mug on top of a window sill
Coffee mug on top of a window sill

Finally, it is important not to overlook a decorative aspect of your window sill. It is a good idea for you to include this feature because they look nice. In the past, virtually all window sills were made of wood. It was easy to get, less expensive to install, and easy to work with. Unfortunately, wood will eventually decay. Even though you may still want to use wood for your window sill, you have other options available.

For example, a lot of people like to use plastic. Some people like to use metal. Those who really want their houses to pop often use marble as a windowsill. You should think carefully about what you are going to put on your windowsill. That way, you can make sure you protect your home from harm while also getting the most out of your window sill.

Carefully evaluate the benefits and drawbacks of every option before you decide which one is right for you. That way, you can make sure you get the most out of not only your windows but also the window sill.

These are a few of the most important reasons why you need to make sure you include a window sill when you are replacing a window. If you do not include your windowsill, the structure of your house is going to be threatened.

What Are the Options for a Window Sill?

When you take a look at the various options available for a windowsill, you need to think about the benefits and drawbacks. That way, you can select the best window sill to meet your needs. A few options available for your window sill include:

  • A Wood Window Sill: This is the first option you have available. If you decide to go with wood, you will have an easier time sticking to your budget; however, you need to make sure you protect your wooden window sill appropriately. Wood is a living organism, and it is susceptible to termites. Therefore, you should seal the wood appropriately to protect it. Furthermore, you may want to weatherproof it to prevent water damage.
  • A Stone Window Sill: You might also want to think about going with a stone window sill. This is an incredibly durable material and it does not require any sealing or treatment. It will stand up to the elements without any issues. You have numerous options available if you are looking for a stone window sill.
  • A Marble Window Sill: You might also want to think about a marble window sill. This is a durable material that can really make the window pop. The downside is that marble can be expensive, but it will look nice if you install it properly.
  • A Tile Window Sill: Tile is not commonly used as a windowsill, but you can use it if you want to. It is commonly found in older homes. You should think about the decorating scheme in your home before you decide if this is right for you.

These are a few of the many options you have available when you are trying to install a window sill. You need to think about the benefits and drawbacks of each option before thinking about your budget. That way, you can select the best option for your house.

Do I Really Need To Have a Window Sill?

Two new construction homes being built - without windows in
Two new construction homes being built – without windows in

After reading all of this information, there are still some people who are going to wonder if they actually need a window sill. The answer is yes. You need to have one. If you do not install the windowsill, your home is going to suffer a significant amount of water damage. Your floors, walls, and ceilings are all going to develop significant wood rot.

Furthermore, your window is not going to last very long. It is going to crack, warp, and you will have to replace it relatively quickly. This is going to lead to a substantial repair bill. You need to think carefully about the type of window sill you install, as this is going to impact how you use it.

If you pick a good material for your windowsill, you can significantly reduce your utility bills while also preventing major repair expenses down the road.

If you planning to put new construction windows in your existing house then they may also require window sills.

Is Replacing a Window Sill a DIY Project?

Yes, it is possible for you to replace a window sill on your own. You need to make sure you have the right materials, which are going to vary depending on what you use to make your window sill. It is also a good idea to take a look at local home improvement stores to see if they have window sills you can install with a few clicks or screws.

That way, you can reduce your chances of making a mistake. If you ever have any questions or concerns about building a new window sill, you need to reach out to a professional who can help you.

Why Do Window Sills Look Like They Are Angled?

You may have also noticed that window sills look like they are angled, particularly on the outside of the home. They have this angle because they direct ran away from your wall and building. During periods of heavy precipitation, an angled window sill is important for preventing water damage.

If the windowsill is perfectly level, water is going to collect on the sill, leading to wood rot. This can damage the frame of the window and impact your home. For this reason, when you are putting together your window sill, make sure it has been angled appropriately.

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About Charlie D Paige

Charlie is a massive DIY fan, with dozens of DIY projects under his belt - ranging from tiling to electrics, and concrete pads to walls. Charlie loves tinkering, seeing how things works, the outdoors and playing with power tools... so is it any wonder that he's completed so many DIY jobs over the years?

Charlie loves spreading his hard-won DIY experience with the world via this blog.