Racked Windows

Check diagonals to see if window is square.  i.e.: if window is “racked” then one diagonal will be longer than the other and the window will not open and close properly.
Insulated glass usually has a glazing bead on the outside but sometimes it is found on the inside or with no glazing bead and the frame must be disassembled to remove and replace the glass.  Some glazing beads are triangular in shape and is removed by depressing the bead to unlock it.  (Often this type of bead becomes brittle and cracks when removed.  After reinstalling glass if the plastic glazing bead has cracked and new bead cannot be located then caulk new glass in with a high grade butyl caulk.)  The flat glassing bead is removed by forcing it away from the stile or rail.  The short beads must be removed first.