Ask the Door Guys | Ask the Experts


How do I measure door size, and  Hinge/ Lock prep locations (for a door-only replacement), to ensure that the new door lines up precisely in the existing frame?



To measure the door, be as accurate and exact as possible. First, measure the inner frame, width and height, to establish the door size you’ll need.  Actual door size is reduced accordingly, to fit the inner frame.  For hinge locations– measure from top of the door, to the top of each hinge pocket. For lock center-line locations- measure from top of the door, to the exact center of the latch plate, on the lock edge of the door. Also check the Backset of the lock  (center of the lock cylinder, or lever hole,  on the face of the door). Standard is 2-3/4”.

** These same measurement can be taken on the door frame ( from under-side of the frame header, to the top of the hinge pockets, and to the center of the lock strike plate.  The differential will be about 1/8” vs. measurements taken on the door, due to the standard gap between the top of the door and   frame header.

*** Manufacturer Hinge/ latch center location charts can also be used as a reference for common manufacturer locations  ( Ceco, Steelcraft, Curries, etc…).  Always measure by hand, though, to be sure! Even being as little as 1/8” or less off on hinge/ lock locations will cause a new door not to fit properly!


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