How to Replace Aluminum Windows

What You'll Need
Measuring tape
Caulk gun
Replacement window

If you decide to replace aluminum windows in your home consider installing them yourself. This is a project for an experienced do-it-yourselfer though. If the window is not installed properly then it can void the window warranty. It can also cause rotting around the windows and this can result in interior or exterior water damage.

Step 1 – Measure the Opening

Measure the opening with the measuring tape. Measure the width at three levels, top, middle and bottom of the window. Do the same to measure the height. If there is more than 1 inch difference between the width measurements or 1 inch difference between the height measurements then you will need to cut strips of wood that are tapered and nail them to the sides checking to be sure that they are level and plumb.

Step 2 – Order the Windows

Order a window that is ¾-inch less than the narrowest width measurement and ½-inch shorter than the smallest height measurement. This is crucial in getting the window to fit into the opening properly.

Step 3 – Remove the Old Window

First pull out the fixed panel of glass. Then remove the fixed panel. You may have to unscrew some screws to get the window out. Next remove the meeting rail. This rail may have to be cut out with a hacksaw. Now remove any trim around the window that will interfere with installing the new window.

Step 4 – Inspect the Window

Take the replacement window out of the packaging. Inspect it for any cracked glass or damage to the frame. Then check to see if it is square by taking a diagonal measurement from one corner to another. Next measure from the two remaining corners. These measurements should be the same to assure that the window is square. If it is not you may want to ask for a replacement.

Step 5 – Set the Window in the Opening

Put a level on the windowsill and see if it is level. Note if it has a high and low side. Put the level up to the sides to check for plumb. Before setting the window into the opening check to be sure you have it right side up and right side out. The weep holes should face to the outside of the house. Put the window into the opening. Place shims as needed to make the window plumb and level. Caulk around the shims to seal them.

Step 6 – Secure the Window

Once you have the window correctly situated nail it into the nailing fin. Test the window by opening and closing it before completely nailing it down. Now caulk all of the gaps and joints in the window frame.

You can save a significant amount of money by replacing windows yourself. Do take your time and do the job right. The process involves a number of steps and accuracy is important. But learning this skill is worth the time and effort involved.