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Window Sill Replacement

window sill replacement

Window Sill Replacement is a job that most homeowners do not want to take on.

It requires the removal of the existing sill, which can be painstakingly difficult without proper tools and equipment.

The new replacement sill must fit perfectly against its original location in order for it to look good as well as work properly at keeping out drafts or water damage. 

Windows are an important part of your home’s appearance and functionality so it’s important to know how to replace them if necessary!

What is a Window Sill?

A window sill is a horizontal framing member that helps to support the weight of the window. It can be made from wood, vinyl, or metal. 

A sash window has either one or two sills depending on the design and style of the window.

The lower sill is called a “bottom rail” or “sill proper” while the upper sill is known as a “transom beam”. 

The upper and lower sills are sometimes combined into one piece known as a “jamb sill”. 

The word jamb refers to the vertical framing members that make up the sides of your window opening, such as:

  • Side jambs (vertical pieces on each side) – Molding that covers the gap between the window frame and the drywall – are usually made of wood or vinyl.
    • Side jambs can be changed by installing a new type of jamb liner, which is often referred to as “sill replacement” in industry jargon.
  • Head jambs (the vertical pieces at the top) – can also be replaced, but this is a more extensive project than simply changing the side jambs.
  • Muntin (horizontal pieces between jambs or other sills) – are another type of jamb liner, but they do not completely enclose the frame.

Possible Window Sill Replacement Materials

If you are looking for a window sill replacement, there are many options available. The materials used to make your windowsill can be made of plastic or wood. 

Each material has its own benefits and drawbacks so it’s important to consider these before making the choice.

Window Sills Made From Wood

If you choose wooden window sills for a new home build they can be made from a variety of wood types. Some good choices include cedar, cypress and redwood.

Wood window sills are popular with homeowners that want to add the exterior charm inside their home as these window sill materials give an authentic look and feel to your windowsill area.

Window Sills Made From Plastic

If you choose to use plastic for your window sill replacement materials then there are some great options available. 

Among the best choices is vinyl which comes in a variety of styles and can be stained to look like real wood.

Plastic gives you more flexibility with design options as it offers color, patterns and textures that create very realistic results without having to stain or paint them yourself.

How to Replace a Window Sill?

It’s important that you remove the window before beginning this job so it won’t be in your way. 

But, if you can’t safely remove the window without damaging it then take precautions to brace it in position.

Start by removing the nails that attach the sash weights to the side jambs, then remove all of the stops and parting beads (if there are any). 

It’s best if you can work with another person because this job is very difficult on your own! Take off each individual window component so you know what order to reassemble them in.

To remove the sill, you’ll have to pry it from its position using a flat bar or cat’s paw tool (be sure not to scratch the wood) and take out any nails that secure it down. 

You can use an electric Sawzall with a metal cutting blade if necessary but be careful not to damage the wood.

Once it’s free, you can replace or reuse your Window Sill depending on its condition and how well it fits in with the rest of your window components. 

If necessary, install a new piece made specifically for this purpose! 

To fit everything back together again you’ll need an adhesive caulk that resists water—such as silicone caulk—as well as nails, screws, and possibly even some wood glue.

Tools on the windowsill

Why is Windows Sill important?

Window sill is the part of the window, which is used to hold up your windows. It can be made out of different materials like wood or metal. 

The reason it’s important is because if you want to replace an old one with a new one then replacing just the entire frame isn’t enough as this will lead to too much damage to your window.

How do I know if my Window Sill Needs to be Replaced?

There are signs when to replace your window. And if you find that your window sill is rotted, peeling, or warped then it’s definitely time to replace it! 

These types of damage may not seem like a big deal but they can cause water (and mold) damage to your walls and floors. 

You may want to consider replacing the rest of your window sills as well if you notice a lot of wear and tear on them too!

How much does it cost to replace the window sill?

Window sill replacement costs about $25 per linear foot for most materials. 

This is a good estimation, but the price will vary from location to location depending on local supplier prices and material availability. 

The cost of hiring someone else to do it is also likely going to be higher than doing it yourself as well.

Windowsill. The cat is sleeping on the windowsill.