Door viewer: The door with eye

To see who is at the door without opening it: Door viewers are primarily used for security and burglary protection. What types are available, how to install them - all this and more is revealed in our guide.


The classic door peephole - almost standard in the apartment building

Everyone is familiar with the conventional door viewer: a hole in the door at eye level - usually with a flap to close it. Current models are equipped with a wide-angle lens that increases the detection angle to 100 to 200 degrees. The concave lens prevents anyone from outside from looking into your home.

In the classic door peephole, the peephole is located in the upper door leaf area. Since there are no mechanical wear parts attached, the classic door peephole is built to last forever. Thanks to this feature, it is now standard in the entrance doors of most rental apartments. Disadvantage of the door peephole: the area outside the door must be illuminated in the evening or in poor lighting conditions in order to be able to recognize something or someone.

Alternatives to the door peephole are door chains or locking brackets as protective hardware, which are rarely found today: They allowed to open the door only a crack. If someone presses against it from the outside, the chain or the locking bar resists.

Digital door viewers - modern technology for homeowners

The digital door viewer is the modern alternative to the classic, analog door viewer. If you have to walk to the door to see who is waiting for you with the classic door viewer, with the digital door viewer you can simply see the image from in front of the door on your smartphone. The camera in the door viewer records the area in front of the door and transmits it in real time to a screen inside or to an app on the smartphone. This makes sense especially for people who are often on the move or people with limited vision or severe visual impairment, or people with walking disabilities or in wheelchairs and for children or very small people.

In addition, the visitor or a possible burglar can not see from the outside whether there is someone in the apartment. Through the classic door peephole, light can penetrate to the outside, which does not happen with the digital door peephole.

Some models are even equipped with a night vision mode. Others record the area in front of the door and save the video recording so that you can also see what is happening in front of your door afterwards.

However, this control can also be a disadvantage, because is recording other people with the help of a digital door peephole even allowed? If you live in an apartment building, the privacy rights of other tenants must be protected. Therefore, most landlords do not accept digital door viewers or only as an exception, for example, for people with disabilities. The problem is that the privacy of other tenants can be violated by the recording. For this reason, door viewers that store the video recording are also not allowed. Therefore, you should always discuss the installation of a digital door peephole with the housing association or landlord.

In your own home, digital door viewers are a real alternative. Here, it is also worth combining them with other devices, e.g. a smart door opener, so that you can let the visitor in directly.

Digital door viewers are usually battery-operated, which is why the battery or rechargeable battery must be replaced depending on its service life. In addition, you need a correspondingly strong door for a digital door viewer, as it is heavier than a classic door viewer.

The Digital Door Viewer as an Element in the Smart Home

In your own home, you can optimally integrate the digital door viewer into an existing smart home system. For example, there is the option of coupling door viewers with voice communication - similar to an intercom system - so that the resident can talk to the visitor. By connecting to a smart doorbell or smart door opener, the door can then be opened as needed. For higher burglary protection or night owls, an outdoor camera with infrared motion detector is also suitable. The disadvantage: Depending on its sensitivity, the motion detector also registers movements of larger animals. You should bear this in mind for houses on the edge of a forest.

Smart Home requires a WLAN signal, so a WLAN router with the appropriate range should be available.

With the help of a smartphone, you can access the door viewer while on the move. If the door intercom is linked to other elements, you can open the door, start the ventilation or control the light in the entrance area while on the move. For example, if the children are coming from school, tradesmen have been announced, or the letter carrier is to leave a package at a drop-off point, these functions prove helpful.

Door viewers not only for private use

Door viewers are used not only in the private sphere, but also by the police or banks, for example, to view a vault. Prisons also use door viewers to keep an eye on prisoners from the outside.


How high does a door viewer need to be?

The door peephole varies in height. Particularly in barrier-free apartments, a classic door peephole can also be installed significantly lower than usual. The standard height in Germany is 140 cm - measured from the lower edge of the door leaf..


Who installs a door viewer?

The classic door viewer is a standard feature in most rented apartments and, thanks to its long service life, can usually remain in the door until a new tenant moves in. In your own home or condominium, it is best to consult a professional for installation. This guarantees that the door peephole is firmly fixed, so that the security of the door remains guaranteed. Cost for the classic door viewer: from 10 euros plus installation.

The digital door viewer always requires professional support. Particularly in the case of integration into a smart home system, the expertise of the experts is crucial. They provide instruction in the functions and expertly answer all questions. Digital door viewers can vary in price from around 70 euros to several hundred euros.

You can find the right door viewer in a DIY store, department store or specialist security technology store - or online. Ask for advice in a specialist store. If necessary, the dealers also offer an installation service.

By the way: As a tenant, you are allowed to install a door viewer in the entrance door of your flat - without the landlord's consent. This was decided by the district court of Meißen in its door viewer ruling (ref. 112 C 353/17).

What you need to look out for when buying a peephole

Door viewers, also known as peepholes, are small but effective security devices that allow you to see visitors from the inside before you open the door. Choosing the right Door viewers can greatly improve your home security. Here are some important Spots to consider before and when buying a Door viewer:

1. understanding the basics

A Door viewer consists of a small lens or optical system that is built into your front door and provides a wide viewing angle to the outside. Modern versions can include digital cameras and displays.

2. choose the right type

There are two main types of Door viewers:

  • Traditional optical Door viewers: these provide a direct field of view through a small lens. They are inexpensive and easy to install.
  • Digital door viewers: These provide a video view of the visitor and can include additional features such as Photo or video recording, night vision and even Wi-Fi connectivity for smartphone notifications.

3. point of view

The viewing angle of a Door viewers determines how much you can see from outside your door. A wide viewing angle of 180 degrees or more is ideal as it allows you to see a larger area outside your door.

4 Installation and compatibility

Check the thickness of your door and make sure the Door viewers you choose are compatible. Traditional optical door viewers usually only require a simple hole to be drilled through the door, while digital models may require a more complex installation and power supply.

5. security features

Digital door viewers can offer additional security features, such as motion detection that automatically takes photos or videos when someone approaches the door. Think about which security functions are important to you.

6. data protection

When choosing a Digital door viewers, it is important to consider data protection. Make sure you choose models that store your data securely and protect it from unauthorized access.

7. budget

Digital door viewers are generally more expensive than their optical counterparts, but offer more functions. Determine your budget and decide which functions are essential for you.

8. user-friendliness

Digital door viewers with a large display can significantly improve user-friendliness, especially for older people or people with visual impairments.

The most frequently asked questions about door viewers

What questions are most often asked about door viewers? We found out using software that analyses which questions people ask voice assistants from Apple, Google and others. We answer three of them here:

1. How much does a door viewer cost?

Classic peepholes are available for as little as 10 euros. Digital door viewers are more expensive.

2. At what height must a door viewer be installed?

Door viewers are mounted at eye level. As a rule, the door viewer is mounted between 150 and 165 cm above the upper edge of the floor. The exact height can be adjusted individually.

3. What is a digital door viewer?

Digital door viewers are equipped with a camera instead of a wide-angle lens to look through. When someone rings the doorbell, the camera transmits the image to a screen in the home. Most digital door viewer systems can also be connected to a smartphone.