Don’t blame your builder for installing those old lightweight hollow-core doors. This type of interior door was the standard for most homes built in that era. Not until the past 10 years or so did door manufacturers begin to offer designer interior doors. Now they are commonplace in new construction.
Here are several interior door manufacturers to contact for their product brochures—Georgia-Pacific, GP.com; Jeld-Wen, Jeld-Wen.com; Madawaska, MadawaskaDoors.ca; Morgan Products, Morgan-Wightman.com; and Simpson, SimpsonDoor.com.
Many home center stores now have special woodworking equipment to immediately cut the holes for the lockset, mortises for hinges, etc. This can make your door replacement a one-day job and ensure that the new door will line up perfectly with the door opening.
If you are doing more than one door, write the location of the door on the old door. It is important that you do not get the doors mixed up because they may not all be the same size.
Now make some very accurate measurements. Be on the side of the door where you can see the hinge pins. Since the latch side edge of interior doors is beveled so they can close without too large a gap, you must measure across this side.
Measure the width of your old door at the top, middle, and bottom and take an average of them. The size will most likely be either 30 inches or 32 inches for common residential doors. Now take a height reading along each edge of the door.
The next critical dimension is the exact position of each of the hinges. Open the door and measure from the top down to the top and bottom of each hinge. Do not measure between hinges because this may just compound any errors.
The final measurements are for the lockset location. Remove the old lockset. First, measure from the top of the door down to the center of the large hole through the door. Next, measure horizontally from the edge of the door to the center of the hole. Take all these measurements to your home center and have the doors milled.
For a more experienced do-it-yourselfer, with a few power tools, consider fitting your own doors. Purchase the doors you need. Remove the old door and lay it on top of the new door, aligning them at the top. Using a sharp pencil, accurately mark the hole and hinge locations.
If you do not want to go to all the trouble of making all these measurements for each door and you do not mind being without your doors for a week or so, just remove your doors and take them to your home center or building supply outlet. Make sure to mark the top end of each door. If you do not, the bevel may be milled improperly.
Locksets are usually available in either a 2-3/8-inch or 2-3/4-inch backset (center distance from the edge of the door). Although your old locksets are probably 2-3/8 inch, consider 2-3/4-inch ones. The extra 3/8 inches means fewer bruised knuckles from hitting the door frame.
