A door entry system is often referred to as an intercom, but these are, in fact, two different types of system.
Door entry systems are comprised of an audio or audio and video panel outside the door with one or more buttons that call handsets within the property, a little like a doorbell with two way speech.
Intercom systems are systems that intercommunicate between different rooms within a building or a group of buildings (some door entry systems do have the facility for the internal devices to communicate with each other much like an intercom system). We are not specifically going to discuss intercom systems, despite their similarities but you can read more about them here.
Purpose of Door Entry Systems
Door entry systems are designed to allow communication between visitors at the door and the resident within the building. This allows the resident to decide to grant or deny access to the visitor.
Door entry systems are most commonly used with apartment blocks. The multi-button panel at the door allows the visitor to call a specific apartment and the resident to grant the visitor access to the ground floor's communal entrance by releasing an electronic locking device.
In this scenario, due to the access required by multiple residents, the door entry panel would likely integrate an access control system, allowing them to access the building through the electronically-controlled door lock.
What to consider when choosing a door entry system
There are many points that must be considered when deciding which door entry system is right for a project, necessitating careful analysis of the site and users' needs.
With the growing popularity of the smart home, there is a requirement for door entry systems that integrate and allow access through smartphone devices. These types of system are mainly wireless technology, but some manufacturers are now providing a wired system with a WiFi interface to allow this smart home connectivity. Of course, technology is ever-evolving, and new methods of connectivity are consistently being brought to market.
Key points to consider
Objective
It is important to be clear on the door entry system's purpose before you consider further points. Is it purely to allow communication between the residents and the door? Is the door protecting a secured area? Does there need to be audit logs of users accessing the building or and at what times?
Size of the building
How many separate residencies are within the building? This will have a bearing on whether you have a number of separate buttons or a digital panel allowing for potentially hundreds of separate connections if it is a large apartment block.
Cost
Cost will always be a consideration for any kind of security system. Be sure to allow for a system the facilitates the control required without including unnecessary features that add unwarranted cost.
Do you need built-in access control?
A single residence scenario that the user requires for security to communicate with a visitor may wish to rely on a manual lock rather than access control with an electric locking device. A single residence with the door entry system on a gate at the end of a drive will need a method of accessing the gate themselves, and so a form of access control would be suitable. A multi-apartment block would require multiple users to access the door both remotely and in order to enter the building themselves. As you can see, this consideration very much depends on the site and its requirements.
Audio or Video?
Door entry systems are available in both audio-only and audio-visual options. Which you choose will primarily depend on the level of security required, but any existing wiring could dictate the type of system it can accommodate as well as additional considerations.
Audio Door Entry Systems
Audio door entry systems rely only on audio verification. The visitor can request access verbally in order to gain entry. This is not as secure as combining with video for audio and visual verification but is a lower cost option and allows the option to connect multiple outdoor panels to the internal handsets. This system works particularly well if there is additional CCTV on the property that gives visual verification of the visitor.
Specialist audio door entry systems are available that utilise the existing telephone infrastructure within a building. The visitor presses the button at the door panel as with any other door entry system, and the audio is transferred to the resident via the telephone line.
Video Door Entry Systems
The addition of video within the door entry system increases security as you can see the visitor requesting access and speak with them through the audio. Video door entry systems work similarly to their audio counterpart with the addition of a camera at the panel. Typically this is a fisheye lens to give a wider view which can be useful if there is more than one person at the entry. If a video entry system is used over IP, the captured video can be stored for later analysis if required.
Wired or Wireless
As with other technologies, door entry systems are available as both wired and wireless options. Wired options could be a dedicated cable infrastructure purely for the door entry system, or it could be an IP based system utilising an existing network infrastructure. IP systems add an initial cost to the project, but the lack of cable installation may negate this.
The type of install is an important point to consider. The reality of the matter is that wired connections are almost always more reliable than wireless which can be affected detrimentally by external factors. However, some situations may not be well suited to cabling a system such as listed buildings. If a wireless system is the best option, you will need to ensure the wireless connections available will operate reliably. Wireless systems would be best suited to premises that have a good WiFi or mobile signal.
Some buildings may have an existing cable infrastructure in place, either using a network or cable from an existing door entry system you might be replacing. If existing cabling is a factor, be clear about the type of cable already installed to ensure the new system will function.
Types of door entry system wiring
There are many different wiring configurations available for door entry systems such as the below.
- Audio Systems - 5 Wire, 2 Wire Analogue, 2 Wire Digital, Wireless, GSM, IP, PABX, Direct Fixed Line, DECT
- Video Systems - 5 Wire & Coax, 4 Wire & Coax, 3 Wire & Coax, 4 Wire, 2 Wire, WiFi, IP, DECT
Style of the door panel
Some properties may require a specific finish to the door panel to integrate into the building structure sympathetically. There are many options available as standard, such as brass, polished steel, brushed steel etc. but sometimes it may be necessary for a bespoke solution such as powder coating in a specific RAL colour.
Panels are available as flush or surface mounted options, single-piece panels or modular systems. Modular door panels are useful as they allow you to choose the system's components and build them into a frame... a hybrid between an off the shelf solution and a bespoke panel.
There are certain circumstances where it may be necessary to provide a DDA compliant door panel. This can be as straightforward as adding a yellow halo around the buttons or adding braille, right up to the addition of a second lower level camera for wheelchair users.
Example - School System
With security and the safeguarding of children being a primary consideration for schools, most will have some form of door entry system and often an integrated access control system as well.
A typical set up would be an external door released from reception using a momentary button to allow a parent into the reception area. There would then be a second set of doors from reception into the main school area that remains locked until the receptionist has assessed their request to enter the school. If there is no reason to allow access, the school remains secured.
How important is a door entry system?
Many businesses won't require the level of security a school does, but businesses have employees and assets to consider in the same way a school considers the students.
As we have mentioned previously, technology is ever-changing and has a consistent impact on our everyday lives with the security industry moving forward arguably more than other industries. This means we need to adapt to our customers changing requirements and evolving systems. Many manufacturers provide a wealth of informative supporting documents such as wiring diagrams, manuals, technical datasheets which is a great way to familiarise yourself with the systems available.
