How to Measure Jamb Depth for Andersen Windows
Open any window shade or shutter to be able to see the interior jamb of the window.
Open the window so that you can see the entire side of the interior window jamb.
Measure the window jamb's depth. This will be from where the exterior brick mold is attached to the window across to where the interior window trim attaches to the jamb. This is normally 4 9/16 or 6 9/16 inches deep. The brick mold is the exterior window trim that attaches to the window jamb. Write down all the jamb's dimensions, and not just the depth, in inches.