Freeman Exteriors

How to Replace a Window Sill

how to replace a window sill

Do you want to spruce up your window sill and repair old damage? Are you hoping to start a cute herb garden and need a better window sill?

This means that it’s time to replace your window sill with a new one that’ll make all your homeowner dreams come true.

If you’ve never replaced a sill before, it can seem like an overwhelming project. We’re here to help guide you through the process. Keep reading to learn how to replace a window sill in as few steps as possible!

Gather the Right Tools

The first place to start is by finding all the necessary tools that’ll make the entire project simple and efficient. Without these tools, it’ll be both difficult to complete the job and it’ll be easier to make avoidable mistakes.

The good news is that many of these tools are things you might already have available in your garage. These sill replacement tools include:

  • Utility knife
  • Measurement tape
  • Chisel
  • Hammer
  • Sandpaper of varying grits
  • Caulking gun
  • Level
  • Safety goggles
  • Protective gloves
  • Wood screws
  • Screwdriver
  • Replacement sill

If you want to create a window sill yourself, instead of buying it premade, there are extra items to get. Wood for the sill and a saw to cut the wood to size. Stains or paint are also needed to make the sill match the rest of your home.

Another thing to keep in mind is the differences between commercial and residential windows. Commercial windows, for instance, will have specific requirements to stay within lawful guidelines. Make sure to do your research beforehand.

With this kind of equipment on hand, you’ll have everything you need to get started!

Remove the Old Sill

The next step is to remove the old sill from the window frame. This might take a bit of strength to break the bond between the window and the sill.

Focus on using a hammer and your utility knife to break apart the caulking sealant that’s binding the sill in place. Once you’ve started to loosen the sealant, you can use a chisel to start prying the sill away from the frame. Take your time so that you don’t cause any damage to the frame itself.

If you’re measuring your replacement sill by hand, you may want to keep the old window sill in one piece. This will give you quick dimensions you can copy over to the new wood.

If you have a premade sill ready to go, you don’t need to be as careful. The old material can get torn up without worry.

Make sure you remove any trimming or wooden support pieces that can get in the way when it comes time to install the new sill. Removing old sills is effortless as long as you take the time to break the caulk first.

Clean the Area

A vital step to producing a beautiful new window sill is to clear away any dust, dirt, or excess sealant from the area. If you ignore this step, it’ll be almost impossible to create a sill that’s flush against the window frame.

Use your utility knife and chisel to remove any remaining pieces from the old window sill. Once the main chunks of residue are gone, use sandpaper to smooth out any hard edges or uneven areas.

Clean the entire area once you’re done so that your new sill has a great foundation. This step also goes a long way in keeping the sill secure in place throughout the years.

Repair Any Damage

It’s not uncommon for there to be water damage and even potential mold growth hiding behind where your old sill used to sit. With it out of the way, now is an excellent time to do a little bit of repair work.

Repair any cracks in the window frame to give the window a brand new lease on life. Fill in any holes that allow outside air to seep in. Repairing window frames will make your window more energy efficient and lower the chance of future water damage.

Don’t forget to wipe down the entire area again after you’re done. Also, make sure to give the repairs ample time to dry before moving to the next step.

Attaching the New Sill

Now that you’re done with all the new window sill preparation, it’s installation time. Either unpackage the new sill or measure out the boards and cut them to size.

This process is simple if you have someone else to help hold the sill in place as you drive in the wood screws. If you don’t have anyone else available, use chairs or a step ladder to hold it up for you. It won’t be as ideal, but you won’t have to juggle as many things at once.

Attaching a new sill isn’t something you can rush. Take your time and you’ll create a sill that looks immaculate.

Secure the Sill

It’s not enough to leave the window sill with only the wood screws to keep it in place. To create a waterproof seal, you’ll want to use your caulking gun to fill in any gaps between the sill and the frame. This provides extra support and keeps outside worries from making their way into your home.

If you plan to place heavy things on your window sill, it’s useful to add wooden supports underneath the new sill. This way, you can put as many potted plants on there as you want.

The last thing to do is to sand away any excess caulking once it’s dry to create a seamless finish!

Sometimes Learning How to Replace a Window Sill Means Asking for Help

Understanding how to replace a window sill often comes with some trial and error. This means that you might end up spending more in the long run as you gain experience with the correct installation methods.

This is why it’s crucial to call for a professional’s help whenever you find yourself needing a helping hand.

We’re here to make sure every step of your window sill replacement goes smoothly. Check out our services to see how we can give your home the picture-perfect replacement it deserves!

Jake Freeman

Jake Freeman

Freeman Exteriors is a family owned and operated general contracting company. We specialize in roofing and commercial renovations. We serve Champaign County, Vermilion County, including Champaign, Danville, Paris, IL and Crawfordsville, Covington, West Lafayette, IN and surrounding areas. Our goal is to be the general contractor of choice through our pledge to maintain the highest quality of standards and workmanship. Give us a call today to begin your next project!

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Fishers, IN 46038

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