How to measure replacement windows

Measuring Existing Wood Windows

The first thing to do is remove the screen and open the window. 
Measure the window width from jamb face to jamb face (see "W" in diagram).
Measure three times, at the bottom, middle, and top of the window in case the old jamb is warped. If there are discrepancies between the three measurements, use the narrowest measurement. Your new retrofit window width is dimension "W".
 

Wood Framed Window (as viewed from above looking down)

 

 

Window height (H) is measured from the bottom lip of the head to highest point on the sloped sill (as shown) Again measure three times, at the middle, left and right sides of the window in case the old jamb is warped. If there are discrepancies between the three measurements, use the narrowest measurement.
Your new retrofit window height is dimension "H".

 

Wood Framed Window (side view)                 

 

 

Measuring Existing Aluminum Windows

The diagram below is of a single-paned aluminum frame window. Begin by removing the screen and opening the window.  This allows you to determine which flange sticks out the furthest. Measure that flange to the same flange on the other side of the window. This will give you the size of the clear opening you will have once you remove all the panels. Measure the widths at the top, middle, and bottom and use the narrowest measurement. Measure the height in the same way in the middle, left and right sides and use the narrowest measurement. Your new retrofit windows size (either width or height) is dimension "D¹" or "D".

Aluminum Framed Window (cross view)

Click here for a printable window measuring guide

How to Determine Window Handing

Handing refers to the direction a window or door opens and is easy to determine. "X" is used to denote the operable panel and "O" refers to the fixed or stationary panel. Window and door handing is always determined looking at a window from the exterior of the home.

Horizontal Sliding Windows: To determine whether you require an XO or OX window simply view the window from the exterior of your home. If you want the sliding panel to be the one on your left choose XO and if the operable is to be on the right choose OX.

Vertical Sliding Windows: Use X and O differently. With single hung windows only one panel is operable and it is always the bottom panel. On double-hung windows both panels are operable. Since vertical sliding windows are preset as to how their panels move there is no need to specify handing.

Casement Windows: are the same except that casement window crank out rather than slide from side to side. So handing in this case specifies which side the hinge is located on. they are called FCL when the hinges are located on the left side of the frame and FCR for when they are located on the right side of the frame. With the graphic representation of a casement the hinged side is always at the pointed side of the dashed arrow.

And of course if you have questions regarding any aspect of the window you're purchasing, our friendly and knowledgeable staff will be glad to help during your order confirmation phone call.