How to Install a Peephole for a Door

Last updated on January 20th, 2016 at 01:46 pm

Peepholes, or door viewers, are small viewing devices which you can fit to your front door to allow you to see who is there, without having to open the door.  If you live on your own, live in a high-crime area, or are simply sick of having to deal with door-to-door salesmen, then fitting a peephole is a good idea.

Once you have a peephole, you can screen callers without having to open the door. This is useful from a safety point of view, and will save you time and hassle too.  You will never have to open the door to an unwelcome caller again.

If you have children that are old enough to spend time in the house alone, teach them to use the peephole before opening the door, and to only let in visitors that are known to them, and that they are expecting.


Tools Needed

Peepholes can be purchased from most hardware stores and locksmiths.  You will find them in the area where locks, door handles and hinges are sold. Adjustable depth peepholes are quite inexpensive, and are a great investment from a security and safety point of view.

  • A tape measure
  • An electric drill
  • An appropriately sized drill bit
  • Gaffer tape
  • The peephole

Time Required: Less than 15 minutes.

Peephole in a door
Photo credit: Lacarita


Installing a peephole is a simple job.  When you go shopping for a peephole, try to find an adjustable one that fits doors of different thicknesses.  In addition, look for a peephole that matches then appearance of your door as closely as possible, or is in a colour that complements your door.

Step 1: Check the packaging of the peephole to determine what size of drill-bit you need to use.  If the packaging does not mention the size of the peephole, measure the diameter of the barrel (not the lens), to figure out what size drill bit to use.

Step 2: Now you need to determine where to place the peephole.  You should put the peephole at eye-level for the shortest adult in your household. Place a mark at this level on the inside of the door, and then measure across the door to find the centre.  In most cases, this should be where you want to place the peephole.

The one exception to this is if you have a door with a narrow central panel.  In this case, you should not place the peephole there.  Put it on one of the deeper side panels instead.

If you’re not sure how high to position your peephole, err on the side of placing it too low.  It’s easier for a tall person to bend down to look through a peephole than it is for a shorter person to try to look through one that is too high for them.

Step 3: Measure the position of mark that you have just placed on the inside of the door, and place some gaffer tape on that spot.  Open the door, and repeat this process on the other side.  Double check the measurements so that you know that they line up perfectly.  Place gaffer tape on the outside too.  The tape will prevent the door from splintering when you drill it, ensuring a clean and professional looking finish.

Step 4: Carefully drill through the door.  Apply light pressure, and try to break through the wood at a slow, steady pace.  If your door is hollow, then you will feel the resistance stop when you break through the first layer of wood.  Keep the drill bit steady and keep drilling until you have broken all the way through the second layer of wood, and the hole goes all the way through the door.

Step 5: Peel the gaffer tape off the door and wipe away the dust. If necessary, sand the inside of the hole to remove any rough edges.

Step 6: Unscrew the peephole so that you have two parts.  Take the part with the lens, and put it through the hole so that the lens is on the outside of the door.  Put the other part (the part with the viewport), on the inside of the door. Hold the outside part steady and hand-tighten the peephole.

Step 7: Use something with a blunt blade to finish tightening the peephole screws.  If you have a screwdriver set which includes large, flat blades then that’s the best choice, but a plaster spatula, scraper, or anything else that fits the hole will do.  Just be careful not to scratch the paint on the peephole while you work.

Step 8: Your peephole is installed.  Now you can admire your handiwork.

Peephole in a wooden door
Photo credit: Kev-shine


As you can see, installing a peephole is easy.  The basic peephole should be suitable for most people, however if a standard peephole is not convenient for you, because you are far taller or shorter than other people in your household, or the hole is too difficult for you to see through, then consider investing in a video peephole viewer.  From the outside, these look just like normal peepholes, but instead of having a standard viewport, they have a video screen on the inside.  This has many advantages – the screen is easier to see, and it’s more discrete too.  When you go to look through a standard peephole, the person on the other side can often see the peephole darken.  With a video peephole, no-one can tell if anyone is on the other side.

No matter what kind of peephole you choose, remember to make use of it every time you come to the door.  Consider also installing a chain for extra security.  If a tradesman knocks on the door, and you are considering letting them in, open the door but keep it on the chain while you ask to see their identification.  Do not let the tradesman enter your property unless you are happy that they really are who they say they are.


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