How to Install an Interior Door

Whether you're starting a room from scratch or just want to replace an old or distressed door, installing a door is easy and fast. This project requires only a few tools, and most can be rented if you don't already own them. Just get started with Step 1 below to learn how to install an interior door.

These instructions are for a prehung door, or a door that's already attached to a frame with hinges. If you have a slab door instead and need to hang your door, see this article instead.


  1. Image titled Install an Interior Door Step 1
    Buy your door. Purchase a door to fit the rough opening in the wall. Doors and door openings are generally standard sizes, generally 24-36". The framed-in rough opening for the door is always around 2" wider than the purchased door (not including the jamb around the door). This allows for adjustment when installing the door to achieve plumb "level".
  2. Image titled Install an Interior Door Step 2
    Start getting things straightened out. Start by drawing a plumb line on the wall. Measure 1/2" in from the rough opening on the hinge side of the door. Using a 6' or 4' level draw a level line down the drywall. You can also use a laser level, which may be easier and more accurate (there are many models that can attach to a wall).
  3. Image titled Install an Interior Door Step 3
    Attach the door installation brackets. Attach 6 door installation brackets to the outside of the door jamb, the wood frame to which the door comes pre-attached. Place a bracket behind each of the three hinges. Attach the remaining three brackets on the the other side of the jamb. The first bracket should be 8" from the top, the next bracket just above the latch stop, and the final bracket 8" from the bottom of the door.
  4. Image titled Install an Interior Door Step 4
    Place the door into the opening on top of blocks or shims. Place 1/2" blocks under the door if a carpet or hardwood is going to be installed or 1/4" blocks if installing laminate. Never place the door directly on an unfinished floor.
  5. Image titled Install an Interior Door Step 5
    Attach the brackets. Using the plumb line on the wall, screw in the top bracket on the hinge side of the door. Then screw in the next 2 brackets using the same reference notch as the first bracket. After the 3 brackets are screwed into the wall using the same reference notch for each, the door is now level. Now check the reveal (gap between door and door jamb) when screwing in each of the final 3 brackets. Start at the top of the door and check the reveal when screwing in the top bracket. Check the reveal when screwing in the final 2 brackets. The door will now be perfectly hung and the blocks under the door can now be removed.
  6. Image titled Install an Interior Door Step 6
    Install the casing around the installed door. The casing, also called the trim, is the strips of wood that hide the joints and some parts of the hinge. Done correctly, the trim will perfectly conceal the door installation brackets. Choose casing that compliments your style and cut it using mitered corners or other styles, depending on your preference.


  • Use The Quick Door Hanger Installation brackets
  • When installing a solid core door, take a screw out of each of the 3 hinges and drive a long 2.5" screw in. This will increase door stability. Shimming door jamb after bracket installation will also greatly increase the strength
  • You may find that you need to tweak the door jamb when adjusting for the reveal (gap between door and door jamb), simply reverse the screw in the bracket, move the door jamb then re-tighten the screw.

Things You'll Need

  • Power Drill
  • Pencil
  • Level 4' or 6'
  • Door Installation Brackets

Article Info

Categories: Doors and Windows