Measure the Existing Door and Doorframe
Take precise measurements of the existing door and doorframe; then remove the hinge pins and lift the existing door out of the doorframe.
Mark and Trim the New Door
If needed, mark and carefully trim the bottom of the new door to fit the existing doorframe. We used a table saw, but a circular saw will also do the job.
Use the Existing Door as a Guide
Place the existing door on top of the new door. Align the top edge of both doors, and use the existing door as a guide for marking the hinge placement on the new door.
Mark the Hinge Placement
Use a speed square to mark the top and bottom of each hinge on the new door.
Measure the Distance from the Edge
On the old door, measure the distance from the edge of the door to the edge of each hinge. Use the same measurements for each hinge on the new door.
Trace the Hinges
Line up each hinge inside the marks on the new door and trace the outline.
Score the Mortises
Prop the new door on its side and use a sharp utility knife to score the mortise for each hinge. Keep a steady hand around any curved marks to make it easier to chisel out those areas.
Chisel Out the Hinge Mortises
Use a steady hand to chisel out the mortises for each hinge. Continue scoring the mortises with a utility knife as you remove layers of wood.
Tap the Hinges in Place
Continue checking your progress as you chisel out the mortises. Use a block of wood to protect the hinges as you tap them in place.
Use a Door Lock Installation Jig
We used a door lock installation jig to bore holes in the slab for the latch and lever. The one shown in the photo screws onto the side of the door and includes two hole saws.
Bore Holes for the Latch and Lever
Use the existing door as a guide to measure the distance from the top of the door to the center of the latch. Then line up your door lock installation jig with that mark. Use the included hole saws to bore holes for the latch and lever.
When you’ve cut about 3/4 of the way through the door for the lever, pull out the hole saw and cut the rest of the way through from the underside. This will help to avoid tearout, which could damage your new door.
Mortise the Latch Plate
The jig we used included a handy template and cutting bit for mortising the latch plate. The bit removed some material while creating an outline for the mortise.
Chisel Out the Latch Plate Mortise
Use a sharp chisel to remove the rest of the material for the latch plate mortise. When all of mortises are created, seal all of the bare wood with a coat of paint that matches the door.
Install the Latch and Lever
Screw the latch and lever in place following the manufacturer’s instructions.
Screw on the Hinges
Mark the center of each screw hole; then secure the hinges in place with screws. Use a self-centering hinge bit to ensure that the screws remain centered as you drive them. Then install the new door in the doorframe. Then repeat these steps for installing all of your new interior doors.