Interior hollow-core closet, bedroom, and bathroom doors are very easy to work with because they're so light. Installing prehung doors takes all the guesswork out of the task because the hinges are already installed and the door is secure in the jamb. All that's needed is plumbing, leveling, shimming and nailing. Replacement doors are a bit trickier. Both these types are easy for a person working alone. Solid-core entry doors might require a helper.
Carpentry Tools and Materials
- Router with a mortising router bit
- Irwin door hardware installation kit
- Wood chisel
- Mallet or hammer
- Corded or cordless drill with drill bit slightly narrower than the hinge screws
- Step stool
- Tape measure
- Tri square
- New hinges and door knob (optional; the existing ones may be used)
- Scrap wood to shim the door off the floor
Door Hinge Mortising
New passage doors are quite inexpensive but require precise preparation because each job is likely to be slightly different. Be sure the new door is the exact dimensions as the old one. Use the old door to transfer the hinge locations with a pencil (the distance from the top hinge to the top and the distance from the bottom hinge to the bottom are usually different).
Trace out the hinge leafs on the edge of the door, being sure the swing is the same as the old one. Put the mortising bit in the router and set the depth to the exact thickness of the hinge. Mortise out the marked areas with the router.
Hang the Replacement Door
This is also called “swinging the door.” These steps are methodical and should be followed carefully because there is zero tolerance for error. First, stand the door up so that the mortised areas are up against the hinge leafs on the jamb.
Measure the height differential to determine how high to shim the door so that the jamb hinge exactly matches the mortise. Shim the door up to that height and mark where the top middle hinge screw must go on the new door.
*Note: The hinge pin offset must match on both the door and the jamb.
Pre-drill the hole and install the screw. Now repeat the process with the bottom hinge. Use the wood chisel and mallet to make any minor mortise adjustments. Now test swing the door; it should fit just like the old one did. Finally mark the remaining screws, pre-drill, and secure.
Install the Door Knob
Use the tri-square to transfer the center of the strike plate on the jamb to the door; this will be the center of the door knob. Set the Irwin door knob template tool to the proper backset and use the included hole saws to drill out the holes for the door knob and latch bolt. Mortise for the latch bolt faceplate.
Now all that's left to do is prime, paint, and install the hardware.
Kelly Smith - Kelly has over 30 years experience as a journeyman carpenter and 20 as a freelance writer and photographer.
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