Home Improvement: How To Replace A Windowsill

Window sill with plants

Just like your front door, windows are an essential part of any home. It can protect you from extreme weather changes and noise from the outside.

Most importantly, properly installed windows have a great effect on the overall ventilation of your home.

Just below most home windows, you’ll find the window sill. While you might think window sills are installed alongside your windows just for decorative purposes, it has other important functions that it provides to your home.

Window Sill and Its Importance

A window sill is an integral part of all windows, especially for homes. Window sills are usually found at the base of the window frame or sometimes at the top. The size of sill varies to your desired dimension as you can choose a smaller or larger size.

To cater to your needs for plant pots and other ornaments, it can be installed internally, externally, or both. Other than decoration, window sills play a vital role in the structure of your window and home.

Here are notable importance of window sills:

Prevents Water From Seeping In

One of the main purposes are to keep water from going into your home. Snow and rain are bad for the window structure, especially if they’re made out of wood.

Window sill with hot drink

If your windows have drywall or metal structure and water seeps in, they’re still prone to molding and corrosion, respectively.

You might consider molds as a stain or just accumulated dirt, but in reality, it may cause health illnesses. In minor cases, allergies, irritation, and colds are caused by molds. In worst cases, it can cause serious infection and inflammation to the lungs.

Additional Support

Window sills also provide structural integrity to your homes. The foundation of a house deteriorates over a certain period of time, which can make the position of your windows out of place.

With a window sill, the windows are prevented from settling or swaying along with the foundation. It can also prevent cracks and maintain a leveled structure for your home and windows.

Energy Efficient

While smart windows are becoming a trend nowadays, without the proper installation and good window sill, they’re still useless.

Properly installed window have a great impact on the overall temperature of your home. It can make your home cooler during summer or warmer during the winter season.

Your HVAC will also be in good condition and you can save more power since it doesn’t need to overwork to maintain your desired temperature for your home.

Replacing A Window Sill

Replacing a window sill is not a simple feat to do. But, don’t worry since there are many step-by-step tutorials online. For instance, The Skirting Board Shop blog and other sites will greatly help in fulfilling this task.

Women replacing window sill

To replace a window sill, here are the things you will need: hammer, chisel, putty, adhesive, utility knife, drill, pry bar, measuring tape, handsaw, hacksaw, nails and screws, pencil, or marker and paint.

If you have all the items listed, you may now move on to replacing your window sills.

Below are the steps:

  • Loosen the old window sill: The first step to remove your old sill is by loosening it up. You may do this by using a knife to widen the gap and remove the layers of paint and adhesive.
  • Trim the edges: After loosening the adhesives, the next thing you’ll need to do is to trim the edges to provide a larger gap for prying.
  • Pry out the old sill: When the gap is wide enough, use the pry bar to remove it. Don’t forget to clean the surface that you pried out to have an even finish for your new window sill.
  • Measure and cut the right size: This is the most important step in replacing a window sill. If your measurements are not accurate, you may end up losing a lot of resources. Thus, carefully measure the dimensions to avoid wasting your materials.
  • Check if it fits: The best way to do this is to provide an overlap to your window and trim it bit by bit to acquire the best fit you need. This will give you control over the thickness and width.
  • Fix it: You can use nails for this step to fix it. But, for more convenience, you can drill holes and use screws so you can easily remove or adjust in case of maintenance and replacement in the future.


Window sills are an essential part of homes. Having them properly installed and maintained improves the overall value of your homes as it protects the structural integrity of your abode. It also provides comfort and worry-free feeling from any unexpected weather changes.