Materials + Tools Needed
Estimated time of completion: 5 hours
- Utility knife
- Pry bar
- Caulking gun
- Drill and drill bit
- Slip-joint pliers
- Reciprocating saw
- Sash replacement window
- Wood putty or filler
Finding Measurements for Replacing Windows
You will need good measurements of your existing opening to determine how big your replacement window should be. Begin by measuring the left and right jambs at the top, middle and bottom of the window. The shortest of these measurements is the window width. Next, measure the distance between the head jamb and sill at the far left side, middle and far right side of the window. The shortest of these measurements is the window height.
Step 1: Remove Window Trim and Head Stop
Now that you have your measurements, it’s time to start removing the old windows that need to be replaced. Score the paint where each piece of trim meets the existing window casing. Slide a flat pry bar behind the inside stops and remove the pieces. Score head stop and gently pull it loose with pliers. Set aside.
To remove the surrounding trim, cut through any paint or caulk between the interior casing and the wall using a utility knife. Use a flat pry bar and a piece of scrap wood to remove the casing.
Step 2: Remove Window Jamb Liner
Raise lower sash, pry back old jamb liner. Repeat with upper sash. Fold the jamb liner at a 90 degree angle underneath the sash. Repeat with the upper sash, folding the jamb liner across the top of the sash.
Step 3: Remove Old Window
Remove old sashes and jamb liner as a single unit.
Step 4: Install New Window Jamb Liners
Nail a liner bracket every 5 inches along each jamb. Attach the jamb liners to the liner brackets.
Step 5: Install New Window Sashes
Install the upper sash into the exterior track of the jamb liner. Open and close the sash to make sure it slides smoothly. Insert lower sash into the interior track and check that it operates.
Step 6: Install Head and Side Stops
Reattach the head stop. Set the nails below the wood surface. Fill the holes with wood putty and touch up with paint.
Reattach the inside stops. Set the nails and fill the holes with wood putty. Caulk the seams and touch up with paint.
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