Mezuzah

There is a positive commandment to set up a mezuzah on every doorpost. A person who is careful with this mitzvah merits a long life and the house is protected. Even though the mezuzah affords a person protection he shouldn't put it up for that reason; he should do it because that is Hashem's will. The details as to which doorways, how the mezuzah should be placed, and the bracha are described below.

How to Put Up a Mezuzah

Preparing the Klaf

1. The klaf should be rolled from left to right. It should be rolled tightly so that the klaf almost but doesn't actually cover the word שדי on the outside of the klaf.
2. The klaf should be wrapped well, usually with saran wrap or the like, so that it doesn't get ruined by the elements.
3. It is proper that the klaf should be positions so that the שדי is facing outward towards the opposite doorpost.

See the Acquiring and Maintaining Stam page for more details about maintaining the klaf.

The Case

1. The klaf should be placed inside a case or a plastic wrap to preserve it and not simply attached to the wall without any case.
2. Ideally the case should be clear so that the word שדי is visible from the outside. If the area is going to be used for changing diapers or getting changed, the case should not be clear.
3. There is a mitzvah to get a nice mezuzah case to beautify the mitzvah of mezuzah.
4. A mezuzah case in which the klaf is inside a container that is separated from the wall by some airspace is valid.

Who Should Put it Up

1. Initially, the homeowner should put it up himself. If he can't do it, he should appoint a Jew to do it in his stead.
2. The bracha only after everything, such as the tape or nails, is prepared so that one can put it up without delay after the bracha. If an agent (heb. שליח; transl. shaliach) is putting up a mezuzah, some say that he should recite the bracha על קביעת מזוזה, while others say that an agent recites the same text as the homeowner, לקבוע מזוזה.
3. Initially one should not have a child or non-Jew put up a mezuzah. After the fact it is valid.

The Bracha

Before putting up a mezuzah one should recite the bracha of "Asher Kideshanu Bemizvotav vetzivanu likboah Mezuzah" - " אשר קדשנו במצותיו וצונו לקבוע מזוזה" . Ideally, the homeowner should put up the mezuzos and recite the blessing. If one puts up several mezuzot at one time one bracha suffices for all of them. In a situation like this one should be careful not to make a hefsek (pause) between mezuzot by talking. If one did speak some poskim would require you to say a new beracha. If he is using double sided tape or glue he should take the mezuzah in his right hand and recite the bracha. If he is using nails and a hammer he should take the mezuzah with his right hand and place it against the doorpost in the correct spot. Then he should hold it with his left hand and hold the hammer with his right hand. Before the bracha he should begin to put in the bottom nail to minimize the delay after the bracha until it is put up.

Which Doorposts Require a Mezuzah with a Bracha

1. A person should recite the bracha upon putting up the mezuzah that indisputably needs a mezuzah with a bracha and then without interruption put up the other mezuzot. There is no need to put up the front door one first.
2. In general, before putting up a Mezuzah in a doorway that is obligated in a mezuzah, one should recite the bracha. However, if one is putting up a mezuzah on a doorway that doesn't have a door or a doorway that leads into an area that doesn't have 4 by 4 amot square, no bracha is recited.
3. In order to be certainly obligated in order to put up the mezuzah with a bracha the doorway would need to meet all ten conditions: The doorway has (1) two side posts, that are (2) at least ten tefachim tall, (3) has a lintel on top, and (4) has a door in it. The room has (5) at least 4x4 amot square space, (6) a roof, (7) is for a private use and not a shul or bet midrash, (8) is suitable for human dwelling, (9) the room is used for honorable activities and not for a bathroom or bathhouse, and (10) it is a permanent structure.
4. If the doorway doesn't have a door a mezuzah is put up without a bracha. If there is a sliding door or another door without hinges there is a question whether a bracha is recited. However, if it is a folding door or even if it has hinges on the top of the door it would still require a mezuzah with a bracha.

Shehechiyanu

1. A shehecheyanu isn't recited when putting up a mezuzah on the doorpost even if it is the first time one is putting up a mezuzah.

Forgot to Recite Bracha Beforehand

1. If someone forgot to recite a bracha when putting up a mezuzah, some say that you can recite a bracha afterwards, while others hold that you can't unless you take it down and put it back up. Some say that one shouldn't take them down in order to put them back up with a bracha.

Replacing Mezuzot

1. When replacing the mezuzot, a new beracha is recited.

Replacing a Fallen Mezuzah

1. If a mezuzah fell down and one is putting it up again one must recite a bracha before putting it up again if the doorway has a door and the room is at least 4 by 4 amot in size.

Returning a Mezuzah After It Was Checked

1. If one took down one's Mezuzot in order to have them checked by the sofer and they were found to be kosher, according to Ashkenazim one should put them back up without a Bracha of Lekvoah Mezuzah. According to Sephardim, one should make a bracha upon putting them back up after being checked by the sofer. If one checks the mezuzah by himself, he need not say a new beracha. If a mezuzah was found to be not kosher, then a beracha is recited when it is replaced with a kosher one. Please note that a bracha is only said when replacing the mezuzah if the doorway has a door and the room is at least 4 by 4 amot in size. (See above #The Bracha on putting up a Mezuzah).

Replacing a Case

1. However, if one took down one's Mezuzah just to put it in a nicer case, one doesn't need to make a new Bracha when putting it up unless it was taken down for several hours so that one stopped thinking about the Mezuzah.

Replacing After Painting

1. If a mezuzah was taken down for plastering or repainting the door for a few days it should be put up again with a bracha.

When to Put It Up

1. Some say that a person should put up a mezuzah right when he starts to live there. However, others hold that one should put it up before one begins to live there.
2. One may put up a mezuzah at night.

Types of Doors

Accordion Door

1. An accordion door where the accordion door opens to the left certainly should have a mezuzah on the right doorpost. If the door opens to the right or both sides if after folding the door there is a tefach between the post and the area of passage, some hold that it is necessary to set up a new post next to the end of where the door folds, some hold it is exempt, and the minhag is to put the mezuzah on the right doorpost.
2. If there is a part of the accordion door with a thickness of a tefach that doesn't move next to the right doorpost, the mezuzah can be placed on this fixed area.

Double Doors

1. Double doors with or without a pole in between is considered a single doorway and needs only one mezuzah on the right.
   1. Some say that putting up an extra mezuzah when a door is split with a pole and really only needs one mezuzah is a violation of baal tosif.
2. Two doorways next to one another that function the same room and people use one door or the other randomly, they are considered one need and only need one mezuzah on the rightmost post. Some hold that they are both obligated in mezuzot as long as there are two different doors.
3. Two doorways next to one another with doors that are attached to the middle pole and the pole is a tefach wide are obligated in two mezuzot.

Revolving Door

1. A revolving door should have a mezuzah on the right side whether the revolving door turns counter-clockwise or clockwise.

Sliding Door

1. A sliding door should have the mezuzah on the right doorpost even if the sliding door on the right side always remains in place.

Type of Rooms and Buildings

Closets, Pantries, and Storage Rooms

1. A doorway is usually obligated in a mezuzah if it has two doorposts that are 10 Tefachim tall and a lintel on top. Here an exception:
2. A small closet, such as a linen closet or electricity closet, that a person doesn't enter and only uses by takes things out of it isn't obligated in a mezuzah. However, if it is a large closet that is 4 by 4 amot and a person enters is obligated in a mezuzah without a bracha.
3. A storage room requires a mezuzah.
4. If there's a storage room such as an attic that you only use twice a year it is considered as though he doesn't use it at all and it doesn't require a mezuzah. However, if it is used more frequently such as once a month then it is obligated.
5. A garage is obligated in a mezuzah without a bracha since it is used for storage.
6. A walk-in freezer is not obligated in a mezuzah. A walk-in refrigerator is obligated in a mezuzah without a bracha.

Bathrooms and Bedrooms

1. A mezuzah should not be put up by the doorway to a bathroom, mikveh room, or a room people wash in and stand there undressed.
2. A bedroom should have a mezuzah.
3. When a couple is together if the mezuzah is on the inside of the door it should be covered with a single covering. If the mezuzah scroll is already covered with a single non-clear cover such as metal or non-clear plastic that is sufficient. However, if the scroll is in clear plastic and the case is clear it should be covered with something non-clear. Some poskim hold that the mezuzah should be covered with a double covering and so even if the case isn't clear the mezuzah needs another cover.
4. According to the poskim that you need a double cover, if the scroll is rolled up inside the case and the case isn't clear, if the covering was put intentionally to be a double covering as is the common custom it is considered a double covering. Some poskim consider that one a single cover and would require an external cover when a couple is going to be together.
5. Accordingly, if the mezuzah wasn't wrapped before it was put in the case or if you follow the stringent opinions above, before the couple is together the mezuzah should be covered with an external covering such as a piece of clothing. Even if the case is clear it counts as a single cover.
6. A laundry room should have a mezuzah.
7. A washing room before a bathroom, if it is used exclusively for washing one's hands when leaving the bathroom it is exempt. If it is used also for other functions such as storage of items or washing one's hands for a meal, and it is the size of 16 square amot, then according to most poskim it is obligated in a mezuzah. Some poskim hold even in such a case it is exempt from a mezuzah. If sometimes people get undressed in this outer room it is exempt.

Shul and Bet Midrash

1. A shul doesn't need a mezuzah unless people live in the shul building.
2. A bet midrash doesn't need a mezuzah but because some rishonim hold that it should have a mezuzah it is proper to put up a mezuzah on a bet midrash without a bracha. The reason that the bet midrash is different than a shul is since talmidei chachamim use it day and night they consider it like their home.

Offices and Stores

1. According to many poskim an office or store is obligated in a mezuzah even if it is only opened by day. However, since some poskim hold that it doesn't require a mezuzah if it isn't used by night in such a case a mezuzah should be put up without a bracha.
2. A factory and bank have the same status as a store for the purposes of mezuzah.
3. Some say that a school requires a mezuzah just as a store does.
4. If a Jew owns or rents an office all of the doorways require a mezuzah, even the office rooms that are designated for non-Jews, as long as the Jew uses the room on occasion.

Elevator

1. Some say that the entrances on each floor to the elevator should have a mezuzah on the right from the elevator to the building. Others hold that an elevator is exempt.

Buses, Caravans, and RVs

1. Buses, cars, and airplanes are exempt from mezuzah since they are moveable and aren't meant for permanent dwelling. However, one should put up a mezuzah without a bracha for a RV if one lives in it like a house.
2. If one lives in a caravan that is stationary for a long time one should put up a mezuzah without a bracha. The mezuzah should be put up after it is parked where it is meant to stay.

Summer House

1. There is an obligation to put up a mezuzah on a summer home or any home that is lived in even for part of the year.

Doorways to Courtyards and Cities

1. The doorway to a courtyard or city is obligated in having a mezuzah on the right side as one enters. In a city that has some non-Jews the city gate does not need a mezuzah.
2. The electrical posts used for an eruv do not need a mezuzah even though they function as doorways.

Apartment Buildings

1. An apartment building that is owned by a Jew should have a mezuzah. However, if it is a jointly owned by a Jew and non-Jew it should not have a mezuzah.
2. The door to the stairwell should also have a mezuzah.

Inner Rooms

1. Every doorway of one's house is obligated in mezuzah. Even if a room has several doorways, each one is obligated in having a mezuzah. If a doorway isn't used for entering it doesn't need a mezuzah.

Cellar Doors

1. The doorpost of a cellar that is lying flat or nearly flat on the ground is not obligated in having a mezuzah.

Emergency Exits

1. An emergency exit or any door only used to exit is not obligated in a mezuzah.

Hospitals

1. A Jewish hospital should have a mezuzah without a bracha.

Structure of Doorframe and Room

Minimum Size of Room

1. A doorway is only obligated in a mezuzah if the room has 4 by 4 amot of space. If there's not 4 by 4 square amot but there is the same amount of area, such as 2 by 8 amot, there is a dispute whether the doorway is obligated in a mezuzah. In such a case one should put up a mezuzah without a bracha, or recite a bracha when putting up a mezuzah in a doorway that is obligated and then put up this mezuzah.
2. If a room is four by four amot even if there large items such as a refrigerator or oven in that room and it is normally there and enables the room to be used normally it is obligated in a mezuzah.
3. A room in the shape of a T or L is obligated in a mezuzah if has an area of a rectangle of 16 square amot (either areas A, B, and C OR B and D in picture). If there is only 16 square amot of area when total the area of the shape it is a dispute if it is obligated in a mezuzah.

One Doorpost

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  Picture #1:End of wall on right side functions as right doorpost

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  Picture #2: End of wall on left side without a right doorpost

1. If a doorway only has one doorpost, such as if the lintel is connected to a wall, if the doorpost is on the right (picture #1), one should put up a mezuzah without a bracha or recite a bracha when putting up a mezuzah in a doorway that is obligated and then put up this mezuzah. If the doorpost is on the left (picture #2), that doorway isn't obligated in a mezuzah.

Ends of Walls Serving as Doorposts

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  Picture #1: Two ends of walls serving as doorposts

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  Picture #2: Both end of walls serves as walls for other rooms

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  Picture #3: Room with right doorpost as end of wall

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  Picture #4: Room with left doorpost as end of wall

1. A room that has two walls coming to an end to serve as its entrance (picture #1) is obligated in a mezuzah. Because it is a dispute one should put up a mezuzah without a bracha.
2. A room that has two walls which turn a corner and serve as walls for other rooms (picture #2) is not obligated in a mezuzah.
3. If the left doorpost is the end of a wall that extends to the left and the right doorpost is the end of a wall (picture #3) that is considered as though there is a right doorpost without a left one and one should put up a mezuzah without a bracha. Others hold that this case is exempt altogether.
4. If the right doorpost is the end of a wall that extends to the right and the left doorpost is the end of a wall (picture #4) that is considered as though there is a left doorpost without a right one and the entrance is completely exempt from a mezuzah.

No Lintel

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  Picture #1: Door with two posts and lintel

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  Picture #2: Door with two posts and no lintel

1. A regular doorway has two doorposts and a lintel (picture #1). If the doorway has two doorposts and there is no lintel but the area has a roof (picture #2), if the roof comes to an edge at the point of the door some say that one should put up a mezuzah, while others hold that doesn't require a mezuzah. Therefore, a mezuzah should be put up without a bracha.

Small Room Opening into Big Room

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  Picture #1: Normal way to walk is from the big room into the small room

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  Picture #1*: Wide room that leads into hallway

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  Picture #2: Normal way to walk is from the small room into the big room

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  Picture #2*: Hallway that leads into wide room

1. If the big room is an entrance into the small room (picture #1), if that entrance is created by the ends of walls and not doorposts, some poskim hold that the entrance is exempt from mezuzah. Some disagree. To avoid the dispute one should put up a mezuzah without a bracha.
2. If the small room is an entrance into the big room (picture #2) that entrance is obligated even if the doorpost is created by the ends of the walls. Other argue that it is exempt from having a mezuzah.

Screen Door Before the Front Door

1. If there are two doorframes one in front of the other if they're within 1 amah of each other it is considered one doorway and one mezuzah on the outermost tefach suffices. However, if there is a space of more than 1 amah, they each require a separate mezuzah.

Doorway in a Room

1. If there are polls or an arch in the middle of a room that creates a doorway, if the two halves of the room are used for the same purpose there is no obligation to put up a mezuzah on the polls, however, if the polls separate the room in two and they are used for different uses then the doorway created by the polls requires a mezuzah.

How the Mezuzah Should Be Placed

Height

1. The mezuzah should be placed at the beginning of the upper third of the height of the doorway but it should be placed at least a Tefach from the top of the doorway. If it is not in the top third it isn't kosher. If it isn't a tefach from the top of the door it should be fixed.
2. If the floor or the lintel are uneven, how do you measure the height of the doorway to put it at 2/3 of the height?
   1. If there is a step within the doorway, the height of the doorway is determined by the place where you put the mezuzah. If the mezuzah is placed in the outer tefach and the step doesn't begin at that point, the height doorway is determined without the step.
   2. If the floor on the left side is lower than the right side, if that area is at least 4 tefachim wide, the height is determined by the left side.
   3. If there is a window beginning in the middle of the doorway the height of the doorway is determined by where the mezuzah is placed. If the mezuzah is placed in the outer tefach and the window doesn't begin at that point, the height of the doorway is determined without the window. However, to avoid any dispute one should put it within the top third of the door if it is determined with and without the window. If the mezuzah is placed under the part with the window the height is determined with the window.

Very Tall Doorways

1. If a doorway is very tall, according to Ashkenazim, one should put up the mezuzah at shoulder height. However, according to Sephardim, one should place it in the upper third in all circumstances.
2. What is considered a very tall doorway for this halacha? Some say that as long as the mezuzah is visible within the normal eyesight it isn't considered too high. Accordingly, some estimate that if the door is less than 8.86 feet (106 inches) it should have the mezuzah at the height of 2/3, but if it is taller than it should have it at shoulder height. Some say that anytime that the beginning of 2/3 of the doorway is taller than one's shoulders, one should put it at one's shoulder height.

Arched Doorway

1. If the doorway is arched there is a dispute whether the height of the doorposts includes the arched section where the doorway has a width of 4 tefachim. Therefore, if there is a small area which is arched and the doorway has a width of greater than 4 tefachim, it is possible to satisfy both opinions by placing it on the vertical section of the door but still within the top third of the doorway. (For example, if a doorway is 90 inches and the top 12 inches are arched and still has a width of tefachim, one should place the mezuzah in the vertical section above 60 inches.)
2. If the height of the arch is more than one third of the height of the entire doorway so that it isn't possible to satisfy both opinions the primary opinion is to place the mezuzah two thirds up the vertical part of the doorway excluding the arch.

Posts that Don't Reach the Ceiling

1. If there are doorposts which are ten tefachim but they don't reach the ceiling and there is a wall which reaches the ceiling the mezuzah should be placed on the doorposts and not the wall (spot ב in the picture).

In the Doorframe

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  Picture #1: Mezuzah on wall in front of door within tefach

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  Picture #2: Inward swinging door with mezuzah behind door within frame

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  Picture #3: Blue mezuzah on thicker post and gold on thinner post

1. The mezuzah is placed on the right side of the doorframe underneath the lintel within a tefach of the outside of the doorframe. The mezuzah must be placed so that it is visible or there is a symbol to indicate that there is a mezuzah. If it can't be placed under the lintel it could be put even before the lintel within the doorframe.
2. If it can't be placed on the doorpost, it should be drilled into the doorpost. If it can't be drilled into the doorpost see the next halacha.
3. If there is no place to put the mezuzah within the doorframe (picture #1), according to Ashkenazim the mezuzah can be placed on the area in front of the doorframe, even not on the material of the actual frame, within a tefach of the doorframe. According to Sephardim it must be placed within the doorframe in front of the door or behind the door (picture #2).
4. If a doorpost has a thicker post and a thinner post which is further towards the outside (picture #3), the mezuzah can be placed on the thinner part (gold mezuzah in picture). Some hold it should be placed specifically on the thicker part (blue mezuzah in picture).
5. If part of the doorpost is blocking more than a tefach of the entranceway, the mezuzah should be placed on the most extended part of the doorpost blocking the door.
6. The mezuzah should not be placed behind the door on the wall next to the doorframe. If it is, according to many poskim, the mezuzah is invalid.
7. If the door swings out and there is no place in the doorpost to put the mezuzah in front of the door, the mezuzah should be placed behind the door within the doorframe.

Outer Tefach

1. The mezuzah should be placed on the outer tefach of the doorpost both for the front door as well as any other door.
2. After the fact it is kosher. If it isn't too difficult one should fix it.
3. When placing the mezuzah on a slant, it is sufficient if part of the mezuzah is within a the outer tefach.
4. If the outer tefach is exposed to sun and rain and it might get ruined, it is better not to leave it in the outer tefach.

Fixed to the Doorpost

1. A mezuzah should be established in a sturdy way so that it won't fall down. Also, it should not be hanging.
2. A mezuzah could be put up with nails, one on top and one on bottom, but not with just one nail. If one put it up with only one nail but it was tightly fastened to the wall and doesn't move it is valid.
3. A mezuzah could be put up with tape or glue.
4. Some say that a mezuzah could be put up with Velcro.
5. Some say that a mezuzah shouldn't be put up with a magnet.
6. The minhag is to put the mezuzah in a case.

Straight or Diagonal

1. While Sephardim place the mezuzah straight up, Ashkenazim place it on a slant, with the top leaning towards the inside and the bottom towards the outside.

Which Is the Right Side?

1. The criteria by which one can determine which side the mezuzah should be used in the follow order. For other opinions of how to order these criteria see footnote.
   1. From Exempt to Obligated: Any door that goes from a place that is exempt from mezuzah to a place that is obligated in mezuzah should have the mezuzah on the right side entering into the place that is obligated in mezuzah. For example, the mezuzah on the front door or back door of a house is always placed on the right side going into the house since the house is obligated in mezuzah and the street isn’t. A walk-in closet which is less than 4x4 amot the mezuzah is put on the right side going from the closet into the room since the closet isn’t obligated.
   2. Entry: The mezuzah should be put up on the doorpost which is to one's right upon one's entering the house. This criteria applies equally to the outer doors of the house to the rooms inside the house. For example, a room that only has one entrance obviously has the mezuzah placed on the right side going into the room.
   3. Usage: If a room has two doorways if one of the two rooms that it connects is used more frequently then the mezuzah should be put up on the right side going into the room that is used more frequently.
   4. Majority of Walking: If the position isn't determined by entry or by which is used more frequently it can be determined by which room people walk from one room to another; if majority of the times people enter in one direction the mezuzah is placed on the right of that direction.
   5. Doorway: If the position of the mezuzah cannot be determined based on which direction is used for entry or which room is used more frequently it can be determined by the door. Since the door generally swings into the room (besides the outermost door of the house) the way the door swings can be considered the way one enters the room and the mezuzah is placed on the right side entering the room. However, if the mezuzah is determined based on the previous factors it doesn't matter which way the door swings.
   6. Doubt: If it is impossible to determine which side to put up the mezuzah based on the criteria of (1) whether the door is used more for entry or exiting, (2) which of the two rooms that the door connects is used more frequently, and (3) the door hinges because the door is used equally for entry and exiting, the two rooms are used equally and there is no door, according to some poskim there is no obligation to put up a mezuzah at all. Some poskim write that one should put up a mezuzah on both sides, but other poskim write that may not do so since it is [Bal Tosif], adding onto a mitzvah.
2. The halacha that the mezuzah is placed on the right side of the door applies equally to a left footed person as well.
3. The side on which the mezuzah is placed depends on the norm of the people who use the house whether they own it, live there, are obligated in mezuzah or not. It doesn't depend on which way the homeowner wants to be the main direction of entry; it solely depends on which direction is used for more for entry in practice by the people who use it.
4. If the mezuzah was placed on the left side of the door it needs to be taken down and put up on the right side with a bracha.

Back Door to Backyard

1. If there's a back door that opens to an enclosed backyard that is completely closed then the mezuzah should be placed on the right side going into the backyard.
2. If the back door opens into a backyard that has a gate to a courtyard or street then the back door should have a mezuzah on the right side going into the house because the house is used more than the backyard. Some hold that the mezuzah is placed on the right side in the direction of whichever way the majority of the time people enter.

Balcony or Porch

1. A roofed front porch that is open to the front yard or street and opens up to the house is obligated in a mezuzah. If it has 4 amot by 4 amot of space it is obligated in a mezuzah with a bracha. If the area it surrounds is 16 square amot, one should put up a mezuzah without a bracha.
2. A roofed porch that has 4 amot by amot of space on the side or back of the house is obligated in a mezuzah with a bracha.
3. A balcony or deck that opens to a house and has no other entrance or exit should have a mezuzah on the right going from the house to the balcony.
4. Even if the balcony is less than 4x4 amot and isn't roofed, according to Sephardim, the mezuzah should be placed on the right side going from the house to the balcony. Ashkenazim hold that if the balcony is less than the equivalent of 16 square amot the mezuzah should be put on the right side going from the balcony into the house. But if it is more than the equivalent of 16 square amot the mezuzah is placed on the right side going from the house out to the balcony.

Walk-in Closet

1. The questions to clarify for whether a closet is obligated in a mezuzah and as to which side the mezuzah is placed depends on the following:
   1. If a closet is 4x4 amot it is certainly obligated in a mezuzah going into the closet.
   2. Most poskim hold that an area that has 16 square amot, even if it doesn't have 4x4 amot in any one place, is obligated in a mezuzah going into the closet without a bracha. It doesn't matter what shape it is in as long as it is usable.
   3. A walk-in closet that is not 4x4 amot and doesn't even have the area of 4x4 amot, according to most poskim it is completely exempt from a mezuzah, though some say it is obligated since it is useful the way it is. Therefore, strictly speaking it doesn't need a mezuzah, but many poskim are strict to place a mezuzah going out from the closet into the room that itself is obligated in a mezuzah. Either way, the mezuzah is put up without a bracha. According to Sephardim, the closet is exempt.
2. A closet that you do not walk into is exempt from a mezuzah.

Having One's Mezuzot Checked

1. One should have one's Mezuzot checked by a sofer twice in seven years, or once in every three and a half years, and it is a pious practice to check them every year during Elul.
2. Some poskim hold that it isn't necessary to get one's mezuzot checked if they are completely sealed.
3. If one's mezuzah became wet one should check it immediately.
4. The mezuzah's of a publicly owned building only need to be checked twice in fifty years.
5. Ideally Ashkenazim should get mezuzot with a ketav (handwriting) that is Ashkenazic and Sephardim the Sephardic ketav. If one uses the other one it is still valid.
6. A Sephardi should have a mezuzah with a paragraph break like the Rambam and not the Taz, which is common in Ashkenazi mezuzot. For a Sephardi it is possibly invalid and should be replaced.
7. It is permitted to check all of one's mezuzot at once and it isn't necessary to take them down and check them one at a time.
8. Before touching the actual klaf of the mezuzah one should wash his hands with a cup as he would do netilat yadayim for a meal.

Rentals

1. If someone is renting a house in Israel he is obligated to put up a mezuzah with a bracha immediately. However, if one is renting outside Israel for less than 30 days isn't obligated to put up a mezuzah and if he wishes to be strict to put a mezuzah he should do so without a bracha. Some say that the Ashkenazic minhag is to put it up with a bracha. If he stays for more than 30 days and he put up a mezuzah previously he should make a bracha upon the mezuzot. Some say that one has to take down the mezuzah after 30 days and put them up again with a bracha. Others say that one doesn't have to take it down to make a bracha upon it. It is proper to take it down check them and put them back up with a bracha.
2. If someone is renting a house for more than 30 days, some say that he is obligated to put up a mezuzah immediately without a bracha. Others hold that one is exempt until after 30 days have passed.
3. Someone renting a bungalow for more than 30 days must put up mezuzah but some hold that no bracha is recited.
4. A yeshiva dormitory requires mezuzot and they should be put up by the yeshiva and not the students.

Proper Behavior When Passing a Mezuzah

1. When one leaves one's house should kiss the mezuzah to remind one of the unity of Hashem, as discussed below. There are different opinions as to how exactly one should behave when passing a mezuzah.
2. When one enters or exits a room one should think about the unity of Hashem, our love for Hashem, and be awakened from the slumber of the vanities of the world. One should think that there's nothing that last forever except knowledge of Hashem, and immediately this will help a person follow the proper path.
3. One should be very careful with the mitzvah of mezuzah because it is a mitzvah that applies to everyone always.

Non-Jew

1. A Jew who owns a building in partnership with a non-Jew according to Ashkenazim is exempt from mezuzah, but according to Sephardim is obligated to put up a mezuzah without a bracha.
2. A person shouldn't give a mezuzah to a non-Jew unless there is a concern that the non-Jew will be hate him for it.

Women

1. Women are obligated in mezuzah.
2. There is a discussion among the poskim if women can ideally place the mezuzot. Many poskim write that it is even ideal for women to put up the mezuzot.

Children

1. Ideally, a child should not place the mezuzah on a doorpost. Sephardim hold that the child should put up the mezuzah for his doorway and when he becomes bar mitzvah'ed it should be taken down, checked, and put up again with a bracha.
2. The doorway to a child's room should have a mezuzah for chinuch.
3. In a room where the baby is changed if the mezuzah is on the inside of the door it should be covered.
4. Even though it is technically permitted to have a child potty in a room with a mezuzah since the mezuzah is covered and above 10 tefachim it isn't proper to do so.

Moving

1. If a person is moving and another Jew is moving in one must leave them your mezuzot. The reasoning is that you shouldn't remove mezuzot is because they are used to serve to protect the house from harm and taking them indicates that you don't care about those moving in or that mezuzot represent that the divine presence resides in the home and that isn't something one should remove.
2. The one moving can charge the next tenant to pay for the mezuzot, but even if he isn't willing to pay one still shouldn't take down the mezuzot.
3. It is permitted to switch more mehudar mezuzot with less kosher mezuzot. It is better to have them checked before switching them.
4. There is an opinion that you may take down the mezuzot if you're going to put them up in another house, however, that opinion isn't accepted as the halacha.
5. There is what to rely upon to take down the mezuzah if it is going to be painted before the next tenant moves in so that they don’t get ruined.
6. If the house is going to be closed up and no one is going to move in afterwards for the foreseeable future one can take one's mezuzot.
7. If someone has a door which he used to use and decides never to use that door again, some hold it is exempt, while most hold it is obligated. If that room has another door and one decides not to use one of the doors ever again, some of the poskim who are strict in the first case agree here that it is exempt.

Links

• Mezuzah on aish.com
• Halachos of Mezuzah on www.vaadmhk.org