How-To Adjust a Window Mortise-Plate

If the mortise-plate for a mortise-type catch is poorly fitted, it makes the catch difficult to use and can prevent it from holding the window closed securely. Remove the mortise-plate and refit it properly.

Unscrew the mortise-plate from the window frame.

Reposition the mortise-plate. Draw around the outside and the inside of the mortise-plate with a pencil.

Use a chisel to adjust the size of the mortise if necessary. Reattach the mortise-plate and check that it fits snugly.