A contractor would use a Window replica rather than full-frame windows intended for new construction to repair an old window.
Old window Replacement Steps
Here is a set of steps to replace old windows with new windows.
Measure Window
Replacement windows require measurements to figure out the new window’s size, and then it must meet your expectations.
Remove Trim and Head Stop
Find the line where each trim piece meets the window casing and score the point where that line intersects. Fraying of the edges of the trim is prevented when you cut the seams.
Remove Jamb Liner
Pry back the previous jamb liner before raising the bottom belt 6 to 8 inches. Next, have the belt do the top sash. Fold the jamb liner under the waistband so that it is at a 90-degree angle. Fold the jamb liner to form an upper belt, and then repeat with the lower strap.
Remove old window
It’s best to remove the old jamb liner and sashes together. Even if you’re capable of lifting the window by yourself, you may find it easier to have someone help you. If you need a hand, have someone stand outside to catch the window as you begin prying outward. You may have to hit the edges of the jambs with a hammer. The window must be loose and ready to fall before you leave the house to assist remove it. Do not strain yourself with inferior lifting methods to prevent back problems.
Insert New Jamb Liner
Every 4 to 5 inches, install a jamb liner bracket. The brackets should all be perfectly vertical before you drive a nail into them. Insert the jamb liners into the liner brackets. There should be an audible ‘pop’ as each liner locks into place.
Install Sashes
Add the top sash to the outside track of the jamb liner, insert it into the way. Make sure the belt is moved freely by testing to see whether it is open or closed. Attach the inner track’s bottom sash and see whether it moves.
Install Head and Side Stops
Put the head-stopping mechanism back in place. When setting the nails into the wood, make sure they are below the surface. Patch the holes with wood putty and then paint over the repaired areas. Make sure to reconnect the inner stops. Use the hammer and nail set to set the pins, and then use the wood putty to fill the holes. Re-caulk the seams and do some touch-up painting.
Remove Casing
To cut through the paint or caulk between the wall and the casing, use a utility knife to remove the case and use a flat pry bar and a scrap piece of wood. Make sure you use slip-joint pliers to remove the screws if you want to reuse the case.
Remove Sash Weights
If you have a wood window with weights, remove the cords or chains attached to the consequences and cut the ropes or chains attached to the importance for the bottom sash. Once you’ve done the same on the top strap, pull down the lower belt. It is necessary to remove the belt weights.
Remove Molding
When removing the caulk, you will have to pry the molding surrounding the window free. If your window has a flange covered by siding, you should know that draughts may get through it.
Remove Stool and Apron
Remove the stool from home. Begin by cutting through the nails. You should also remove the apron, which is attached to the wall directly below the seat.
Pull Out the Window
If you need a hand, have someone stand outside to catch the window as you begin prying outward. You may have to hit the edges of the jambs with a hammer. The window must be loose and ready to fall before you leave the house to assist remove it.