Since interior doors usually weigh less than comparable exterior doors, the door is easier to move, cut to size and install. One person can usually handle the installation. This installation was made even easier as the door to be installed fit a 24” wide opening. Never the less, the installation of a narrow width interior door still requires the same effort as a four-foot solid oak entry door.
Before installing a replacement door, look at the how the door fits into the jamb. Does the door appear to fit squarely in the jamb? If the answer is yes, then for most installations, the original door can be used as a template for the replacement door. Even if the door is not exactly level or plumb, the human eye in most instances cannot identify the variation if the variation incorporates both the door and the jamb.
If the door does not appear to fit squarely in the jamb, there are several ways to check.
The first way to check an existing door installation is to use a “torpedo” style level and a tape measure. With the door open, place the level against the lock edge of the door at the top, middle, and bottom. Is the door plumb, meaning is the door edge vertically level at each of the locations? Then place the level on the top of the open door. Is the top of the door level at both edges?
Next, check the approximate shape of the door with a piece of string positioned diagonally across the door from the top right to the bottom left. Tie a knot in the string to identify the position and place the knotted end at either the top left or bottom right and extend the string diagonally. If the distance is very similar, then the door is probably rectangular. If the dimensions are not similar, the door is not rectangular.
A third way is to measure the two legs of the jamb and determine if they are the same length. Use a large square to determine if the jamb legs are perpendicular to the header.
For this installation, unfortunately the door did not fit the jamb very well. The jamb was taller at the left corner by more than one-quarter inch and the door was approximately one-quarter inch wider at the bottom than at the top. In fact, the door opening was approximately 24-1/8 inches at the bottom and under twenty-four inches at the top. To complicate matters even further, the floor was tile, not padding and carpet. This made the overall height of the opening approximately 80-3/4”, approximately one-quarter inch larger than the standard 80” door. Door manufacturers recommend that the opening at the base of the door should not be greater than one-half inch tall.
To solve this problem, and have the installed door appear to fit in a square opening, the top of the door needed to be cut at an angle to compensate for the header variation. In this example, the top of the door was cut off, measuring down approximately one-quarter inch on the right (hinge) side in order to raise the door on the left (lock) side.
Once the top of the door has been cut, place the door in the opening to see how it looks. The door slid into the opening; however it was very tight at the top, gradually becoming almost the proper size at the bottom. Remember: When installing a door, the recommended gap between the legs of the jamb and the door edges is one-eighth inch.
Next, use a hand plane to shave the upper portion of the lock side of the door to create a gap of approximately 1/32” running the entire length of the lock side of the door. Use a jointer to finish the gap at approximately 1/8”.
The distance was measured for the 3-1/2” hinges. The door was raised to the proper position and the edges of the jamb hinge cutout were transferred to the door. A mark was made on the exterior face of the door. Marks were also placed on the hinge side of the door indicating the direction of the hinges. These two marks would ensure that the modifications made to the door were on the proper sides as well as position the hinges in the proper direction. The door was moved out of the jamb.
The solid construction of the Pro-Lok Killer Jig makes it a versatile cylindrical/tubular lock installation kit.
This modification provided the capability of a deadbolt and dead latch in one lock (mortise) mechanism while maintaining the integrity of the door.