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Replacing Home Windows

If the windows in your home are damaged beyond repair, or they’re old and aren’t as energy efficient as you want them to be, then it’s time they get replaced. To save some money on labor fees, you can easily replace them yourself. This project is relatively simple, it will just take some time and patience.
There are two options when choosing replacement windows for your home: Sash replacement kits, and wood or vinyl replacement inserts. Sash replacement kits are only meant to replace the upper and lower sashes in double-hung windows. Wooden or vinyl replacement inserts are self-contained window units that include their own jams and sashes, and can be ordered as double-hung, casement, or sliding windows. In this article, we will be discussing how to install wood and vinyl replacement inserts. They are much more common and far easier to install.


Here are the tools you will need to collect:
• Measuring Tape
• Stiff Putty Knife
• Small Pry Bar
• Utility Knife
• Pliers
• Screwdriver
• Chisel
• Hammer or Mallet
• Polyurethane Caulk
• Wooden Shims
• Screws
• Drill
• 4d Finishing Nails
• Fiberglass Insulation
• Vinyl Filler Strip

Measure the Existing Window
The first step in replacing your existing window is measuring it so you can order the right sized replacement. For the best results and easiest installation process, it is vital that the measurements you take are precise. Using a measuring tape, you will need to find the width, height, and depth of the window. Measuring inside the jams, take each measurement in three places. Take the width measurement at the top, middle, and bottom of the window. Take the height measurement at the far left, center, and far right. And then take your depth measurement on each side of the frame while the window is open. The smallest of each of your measurements is called the “rough opening measurement”, and these numbers are what you will use to order the new window inserts. For more in-depth detail, click here for a step-by-step guide on how to measure home windows for replacement. Measuring Home Windows

Remove the Existing Window
Once you order your replacement window inserts and have them on hand, you can begin removing the old windows. Unlock the windows and remove the top and bottom sashes. Score the joint between the window frame and the interior stops with a utility knife to reduce paint chipping. Then by using a small pry bar as a lever and a stiff putty knife as a wedge, gently pry the interior stops away from the frame. Remove any visible nails with a set of pliers. The parting stop is usually caked with paint, so it may require pliers and a chisel to remove. Don’t worry about damaging the parting stop, as the replacement window will come with a new one. Then, complete the removal by unscrewing any visible hardware with a screwdriver.

Install the New Window
Start the replacement by testing the fit of the new window into the existing frame. The insert should be slightly smaller than the frame to allow for shimming and a squared fit. If the window insert fits the opening, then you can begin the installation. Run a bead of polyurethane window and door caulk along the back side of the window stool and along the inside of the blind stop. Then place the bottom of the window insert on the stool and tilt it upwards until it fits inside of the frame. Press the new window firmly against the blind stop to create a seal.


To begin the shimming process, loosely screw the insert into the frame on the lower left and upper right corners. Close and lock the window and measure it diagonally from corner to corner on both sides. The goal is to achieve a squared fit, which means that these two measurements should match exactly. If the window is not squared, then it will not open and close properly once installed. If the measurements are not a match, then slide thin wooden shims in between the insert and the frame to adjust the placement. Keep adding shims and measuring diagonally until you reach a squared fit. Then finish screwing the insert into the frame and cut off any excess shim length with a utility knife.

Seal the New Window
The final step in this process is to seal and trim the replacement window. Start by reinstalling the interior stops to the inside of the window with 4d finish nails. On the outside of the window, fill any openings with fiberglass insulation. Use strips of vinyl filler to cover the insulation. Then use caulk to seal the window along the blind stop and between the windowsill and the filler strip. Then take a step back and admire your work. You have successfully replaced your window! Now repeat the full process for any further window replacement projects.

Measuring Home Windows for Replacement