The Mezuzah is affixed on the right-hand side of the door as you enter the room. It should be placed at a slight angle, with the top of the Mezuzah pointing toward the inside of the room and the bottom pointing toward the outside.
The proper place for the Mezuzah is at the bottom of the top third of the doorway. In other words, measure the height of the doorway and divide by three; then align the bottom of the Mezuzah with the point two-thirds of the way up the doorpost (see illustration). In most homes, the doorways are approximately 78 inches high, so the bottom of your Mezuzah should be no lower than 52 inches from the floor.
If your doorway is much higher (say 90 inches or higher), affix the Mezuzah at shoulder height, even if this is lower than the upper third of the doorway. If the doorpost is very low, a rabbinical authority should be consulted in order to determine where the Mezuzah should be mounted.
If the doorpost or archway is wider (thicker) than a handbreadth (approximately 3¼ inches), the Mezuzah should be mounted within the outermost handbreadth of the doorpost, rather than in the center. However, if there is a protrusion (such as a jamb) running along the height of the doorpost, some rabbinical authorities advise affixing the Mezuzah on the protrusion.
The Right Side
There can be confusion as to which is the “right side” of the doorway. Is it the right as you enter a room or as you exit? And what about a doorway that is between two rooms (e.g., a doorway between a kitchen and dining room)?
The basic rules are:
- For the door at the entrance of the house, the right as you enter is always considered to be the right side.
- Inside the house, if the doorway can be used as an entrance from either side, the right side is determined by how the door opens. Whichever room the door opens into is considered the primary room, and the Mezuzah is placed on the side that is on the right when entering that room.
The laws defining the terms “entrance” and “exit” are many and complex. If there is no door, if there is a swinging or sliding door, or if you are in doubt that you affixed the Mezuzah correctly, it is advisable to have a reliable rabbi visit your home to determine the correct location for the Mezuzah.
When one has young children and they cannot reach the Mezuzah to kiss it, the Mezuzah should still not be placed lower than the top third of the doorway. Instead, you can lift your children up to the Mezuzah or keep a stool nearby so they can reach it on their own. Doing this provides an opportunity to instill in them—and yourself—a valuable lesson: if an ideal is beyond your reach, strive upwards towards it instead of compromising the ideal.
When There Is No Room
There are cases when it is physically impossible to affix the Mezuzah on the inside of the doorpost itself—for example, a swinging door interferes with the placement of the Mezuzah.
In such a case, the preferred approach would be to make a groove that is less than a handbreadth deep, and place the Mezuzah in the groove.
If that is not possible, then it would be permitted to affix the Mezuzah behind the door, provided it was placed on the doorpost.
When necessary, it can be put on either the inner or outer side of the doorpost, as long as it is within about three inches from the opening of the doorway.
You may also place the Mezuzah on the inner side of the doorpost if you are genuinely concerned that it will be stolen or defaced were it to be mounted on the actual doorpost.