How to Measure for Replacement Window

If you are a do-it-yourself handiperson, chances are you are both detail oriented and determined. These are two good qualities to have in order to tackle the job of replacing that broken window.

It does not matter if this is your first time to replace a window or if you are an old pro at it; whether a professional or home improvement novice, one of the first things you must consider is the size of the existing window.

Things You'll Need

• Tape Measure
• Puddy knife
• Pencil and pad
• Possibly a ladder

Instructions

1. 

   Remove Screen First
   If your window has a screen, remove this before attempting to measure.

2. 

   If you are simply measuring for a window replacement quotation, all you have to do is measure is the glass at its lowest point at the bottom to its highest point at the top for height. Do the same, from one side of the glass to the other for the width. Simply tell your glass replacement company your estimated measurements and they will take it from there.

   If you are going to replace the window without the help of a professional, you must get the exact measurements of the glass you will be replacing before going any further.

3. Where To Begin With the Measuring:
   Be sure to measure your existing window from the inside of the house, not the outside.

4. Measure Width first:
   Run tape from one side of the window jamb to the other side of the window jamb. You will be measuring from the inside of one jamb to the inside of the opposite jamb. If the window you are replacing is very old, measure from side to side at three different locations along the width of your window.

   Over the years windows may warp. Even new houses, when they begin to "settle" may cause windows to expand or otherwise change shape. Take measurements at the bottom, middle, and top of your existing window. If all measurements are not the same, choose the smallest one as most accurate.

   Write this measurement down.

5. Measure Height:
   Repeat the same steps, but this time vertically. Measure from the inside of the window sill (that is, top) to the inside of the top window jamb (that is, its bottom-most face). Measure left, middle, and right, and choose the smallest measurement.

   Write this measurement down.

6. 

   Measure Thickness
   There are different thicknesses to consider when ordering or purchasing a window for replacement. Be sure to know the thickness of your existing window.

   Measure thickness by placing a puddy knife under the window stop. Mark the knife at the point that it stops. Take the puddy knife out and measure the thickness.

   Write this measurement down.

7. Now that you have both height and width measurements, you are ready to go glass shopping for your window. CONGRATULATIONS ON A JOB WELL DONE!

Tips & Warnings

• If there are discrepancies in your three different measurements, you will go with the smallest measurement so that the replacement window will fit in your opening. Any existing gaps can be filled in later.

• If your window has broken into pieces or shattered in anyway, take extreme caution. Get a thick pair of gloves from your local hardware store and begin taking the pieces out from the inside of the window. Be sure to clean up good when you are done.