Replace an interior door

Replacing a door in an existing door frame is easier and much cheaper than pulling out the trim and frame and installing a prehung door, because you have the old door as a template.


You can save yourself time and money by installing a new door in the existing jamb and leave the trim intact. Hanging a door is easier than you think. All you need is a hammer and chisel, clamps, a square, drill/driver and assorted drill and screw bits, and a hole saw. Measure the width of the old door. Sizes are all standard, so you’ll be able to find a replacement at your local Builders Warehouse.

Carefully align the top and hinge edges of both doors and clamp them together. Work on a flat, level surface - or floor- to ensure that you get the correct measurements when placing the old and new door together.

If the new door is longer than the old, you may need to sand or plane the top and bottom edges to fit. You can mark any difference while the doors are clamped together.

Cutting the bottom of a door

To cut off a door without splintering the finish, use a guide and sharp blade in a circular saw, and deeply score the cut line with a utility knife. Put a sharp blade in your circular saw, score the cut line and clamp on a straight edge for a guide. Set the guide so that you cut slightly to the waste side of the scored cutting line. Lightly round off the finished edges with sandpaper.

If you're using a jigsaw to cut the bottom of a door, wrap a strip of masking tape about the scored line to make it easier to follow and cut a straight edge.

After making any height adjustments to the new door, clamp together once again and then use a speed square and a sharp pencil to transfer the hinge locations to the new slab.

Unscrew the hinge and tape it in place to trace the rest of the hinge outline. Be sure to match the distance from the edge of the door to the edge of the hinge (the same as it was on the old door).

Use a hammer and wood chisel to cut out the opening for the bracket, leaving the corners for last. Use a sharp utility blade to score around the corner radius and then use the chisel to op out the corner section.

The angle of a chisel determines how deep it will cut. For removing only a small amount, hold the chisel at a low angle, or slightly above the surface.

Mount the hinges on the new door and hang the door. If you don’t need any further adjustments, remove the door again, then finish it to match the rest of the woodwork and rehang it. Now it’s on to the next item on your fix-it list.