How do I determine the handing on my casement windows?

What is meant by "handing" on a Case-master casement window?
What is meant by XO, OX, OXO, XOX handing on my windows?
What is the most common error made on casement window parts ordering?


Frequently Asked Questions (FAQs) about Casement Windows


NOTE: Handing of casement window operators is one of the most common home owner errors - please pay close attention and determine proper "handing" as we do not exchange units without charge. For example, look at the casement window sash lock - if the sash lock is on the left side of a casement window - THIS IS A LEFT HANDING UNIT. Most casement hardware, which includes locks, operators and hinges are handed based on the sash lock location when viewed from the interior - Not The Location of the Crank Handle.


  • How to Determine Window 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. XO 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. 


If you have questions or need help?