Digital locking systems – security and technology in modern buildings

Access control has moved on from mechanical keys to advanced digital solutions controlled by mobile phone or biometrics. As the technology has matured, more and more property owners and businesses are choosing to install digital locking systems. But how does this actually affect security, and what pitfalls should you be aware of?

Why digital locking systems are growing in popularity

Several factors are driving the shift towards digital access control in both residential and commercial properties.

Convenience for users

With a digital locking system, tenants and staff no longer need to carry heavy bunches of keys. Many modern systems use the mobile phone as a key via Bluetooth or NFC, so you always have access as long as you have your phone with you. The problem of forgotten keys simply disappears.

Simpler administration

For property owners and businesses, digital locking systems make life much simpler:

• When someone moves out or leaves the company, you no longer need to collect keys or change locks
• You simply remove the person's access rights in the system
• New tenants or employees get access immediately via the app or a card
• All key management is handled digitally, without meeting in person

Flexible access rights management

A modern access control system makes it possible to give different people different levels of access:

• The cleaning company only has access during daytime hours on weekdays
• Suppliers can be let into the loading bay but not into the offices
• Tenants only have access to their own floor and the communal areas
• Time-limited codes for contractors carrying out a repair

Traceability and logging

Every entry is recorded automatically. This means you can see exactly who opened which door and when. In the event of an incident or suspicious activity, you have a digital trail to follow. This is particularly valuable for organisations with high security requirements.

Cost savings over time

Different technologies for digital locking systems

There are several technologies for digital access control, each with its own strengths and weaknesses.

Keypad locks and PIN codes

The simplest form of digital locking system is the keypad lock, where the user enters a personal code to unlock the door. These systems are inexpensive to install and easy to use, making them suitable for smaller properties or individual doors.

Advantages:

• Low initial cost
• No credential to carry
• Works without a smartphone
• Simple installation

Disadvantages:

• Vulnerable if codes are shared or someone watches you enter the code
• Requires regular code changes to maintain security
• Harder to trace who has used a shared code
• Remembering several codes can be impractical

Modern keypad locks can, however, be combined with app control so that you as administrator can change codes remotely and view logs showing when the door has been opened.

RFID cards and tags

RFID-based access control systems use cards or tags that are presented to a reader. The technology is well proven and used in many office environments and residential buildings. Entry is quick and smooth, cards can easily be deactivated if lost, and the cost per user is relatively low.

There is a risk of cards being cloned, although modern encrypted cards reduce this risk. Users still have to carry a physical card, which can be seen as a drawback compared with mobile-based solutions.

Bluetooth and mobile-based systems

Mobile-based locking systems have grown rapidly in popularity. Here your smartphone acts as the key. Security is high thanks to encryption, and the user only needs to carry their phone. New users are given access via an app, which simplifies onboarding.

Many systems also allow guest access with time-limited digital keys – ideal for Airbnb lets or visitors to a business. The drawback is that the system requires the user to have a Bluetooth-enabled smartphone, and phone battery life can become a limitation.

Biometric systems

The most advanced digital locking systems use biometrics. Fingerprint, facial recognition or iris scanning offer very high security because they are difficult to forge. There is nothing to lose or forget.

Comparison of biometric methods:

On the other hand, costs are higher for both hardware and installation. Some systems perform less well in extreme weather conditions, and biometrics may raise privacy concerns for some users. Biometric access control is mainly used in high-security environments such as data centres, laboratories or sensitive business premises.

Hybrid systems

Many modern digital locking systems combine several technologies. For example, a system might offer:

• RFID cards as the primary method
• Mobile key via Bluetooth
• PIN code as backup
• Biometrics for particularly sensitive areas

This provides flexibility and ensures users always have an alternative if one method fails.

Electric strikes – the key component in access control

When talking about digital access control, the electric strike is a key component. An electric strike is the electromechanical lock that actually keeps the door closed and releases it when the correct authorisation is given.

How does an electric strike work?

The technology is based on electromagnetism. When current flows through the electric strike, magnets are activated that hold a metal plate in place. When an authorised user is identified, the current is cut and the door can be opened. Some electric strikes work the other way round and are normally open – they only lock when power is applied.

The electric strike is integrated with your digital locking system and communicates continuously with the reader and the system controller. When the reader verifies an authorised user (via RFID card, mobile key or biometrics), a signal is sent to the electric strike, which releases the door.

Holding force and applications

Holding force is measured in kilograms or newtons. External doors and high-security environments require a higher holding force, often 500 kg or more. A standard office door can often manage with 300 kg. The choice of holding force depends on:

• Door type and weight
• Traffic intensity (how often the door is used)
• Required security level
• Whether the door is used as an escape route

Fail-safe or fail-secure

This determines what happens during a power failure. Fail-safe electric strikes open automatically and are used on escape routes where people must be able to get out in the event of a fire. Fail-secure electric strikes remain locked and are used where security takes priority over evacuation.

Weather resistance and environment

Electric strikes mounted outdoors need an IP rating that can withstand rain, frost and temperature fluctuations. IP65 or higher is recommended in harsh climates. For indoor use, IP20–IP40 is often sufficient.

Integration with other systems

The electric strike must be able to communicate with:

• Your access control system and readers
• Fire alarm and security systems
• The building's other security systems
• Door entry system or video intercom

In residential buildings, it is common to combine electric strikes with a door entry system so that tenants can let visitors in via the app or by pressing a button in their flat.

Security challenges with digital locking systems

Although digital access control offers many benefits, it also brings new security risks that do not exist with traditional locking systems.

Cyber security and hacking risks

A digital locking system is essentially a computer connected to the internet or a local network. This makes the system vulnerable to cyber attacks.

Common threats to digital access control:

• Weak passwords – Many systems are supplied with default passwords that users forget to change
• Outdated firmware – Known vulnerabilities are left open without regular security updates
• Man-in-the-middle attacks – Communication between app and lock can be intercepted if encryption is weak
• Ransomware and sabotage – Attackers can take control of the entire access control system
• Replay attacks – Someone records and reuses the signal from a valid card or phone

How to protect your digital locking system

Change all default passwords immediately on installation and use strong, unique passwords for administrator accounts. Enable two-factor authentication wherever possible. Schedule automatic security updates and review security logs regularly. Isolate the access control system from other networks where possible, and choose suppliers with a documented security track record. Have an incident response plan for security incidents.

Physical security

Digital locking systems can also be subjected to physical attacks.

Hardware tampering can occur if the reader is mounted outdoors. Someone may try to open it and get at the electronics. Vandal-resistant readers with high IP and IK ratings are therefore important.

Power cuts create uncertainty. What happens if the power goes? Fail-safe electric strikes open automatically, which can be a security problem in some environments. Battery backup or emergency power is needed for critical doors.

Backup solutions often take the form of a mechanical key cylinder. If this is not properly protected, it becomes the weak link in the system. Restrict access to the backup key and store it securely.

User error and social engineering

The technology can be as secure as you like, but people make mistakes.

Common security weaknesses:

1. Code sharing – Tenants or staff share their codes with friends or family
2. Phishing – Attackers pose as IT support and trick users into handing over their login details
3. Tailgating – People slip through a door straight after someone with legitimate access
4. Notes with codes – People write their codes down in visible places
5. Unchanged temporary codes – Cleaning companies or suppliers are given codes that are never changed

Protective measures:

Train users on security risks and the policy on code sharing. Use time-limited guest keys instead of sharing personal codes. Install sensors that detect if more than one person passes through. Make it clear that personal access must not be shared. Implement automatic alerts for abnormal usage patterns.

Privacy and data protection

Digital access control systems log every entry, generating large amounts of personal data. Under GDPR, this data must be handled responsibly.

GDPR requirements for access control systems:

Property owners and businesses that breach GDPR risk significant fines from the relevant data protection authority. Fines can be substantial depending on the severity of the breach.

Digital locking systems in residential buildings

Installing access control in a multi-occupancy residential building brings both opportunities and challenges.

Benefits for property owners

Simpler letting process

New tenants can receive a digital key immediately without having to meet you in person. Ideal for modern letting services and for tenants moving in at inconvenient times.

Less key administration

No more:

• Keeping track of key copies
• Key handovers at move-out
• Emergency lock changes when keys go missing
• Disputes over lost keys
• Costs for new locks

Better security

You know exactly who has access to the property at any given time. If something happens, you have complete logs to review.

Value-added services

Offer tenants modern solutions:

• Parcel lockers with digital access
• Bookable guest rooms
• Laundry rooms with app control
• Shared spaces that can be booked by mobile
• Letting visitors in digitally via the door entry system

Benefits for tenants

Convenience

No heavy bunch of keys to carry around. Your phone is all you need to get into the building, your flat and all communal areas.

Flexibility

Easily let visitors or tradespeople in via the app, even when you are not at home. Give your child a digital key that works even if their phone battery is flat.

Peace of mind

There is no risk of keys falling into the wrong hands. Access rights can be revoked immediately if a phone is stolen.

Less hassle when moving

No more stress about returning keys and waiting for the final inspection. Your access is removed automatically on the day you move out.

Challenges to manage

Digital divide

Not all tenants are comfortable with technology. Older people or those without a smartphone may find the system complicated.

Solutions:

• Offer alternatives such as physical RFID cards
• Provide a code as a backup option
• Give a thorough introduction when tenants move in
• Provide clear instructions in several languages
• Offer good support that tenants can call

Connectivity and reliability

If the system requires an internet connection and the server goes down, nobody can get in.

Solutions:

• Choose a system with local backup
• Have an offline mode that works without internet
• Redundant connectivity via 4G/5G as backup
• Mechanical key as an emergency solution

Initial cost

Installing digital locking systems throughout a property is an investment. For a residential building with 30 flats, the costs might break down as follows:

Hardware:

• 5 digital locks with electric strikes (main entrance, basement, laundry room, bicycle store, bin store): the largest hardware item
• RFID readers and controllers
• High holding-force electric strikes
• Network equipment

Installation:

• Electrician and locksmith
• Configuration

Software:

• Licences

Total initial investment: hardware, installation and software combined

Ongoing costs:

• Support and licences: monthly subscription
• Maintenance: annual cost

Annual savings:

• Key management
• Lock changes
• Administration time
• Total savings: typically well above the ongoing costs

Payback period: approximately 3 years

Integration with existing infrastructure

In older properties, running new cables or installing network equipment can be complicated.

Alternatives:

• Wireless systems that communicate via Wi-Fi or mobile networks
• Battery-powered locks that require no cabling
• Powerline technology that uses existing electrical wiring
• Professional site survey before installation

Digital locking systems for businesses

Businesses often have more complex access control requirements than residential properties.

Zoning and access levels

In an office environment, you will want to divide the building into different security zones.

Level 1: Public zones

• Reception and waiting area
• Meeting rooms for external meetings
• Canteen and communal areas
• Toilets
• Accessible to visitors with limited access

Level 2: General office areas

• Open-plan offices
• Standard meeting rooms
• Staff break rooms
• Printing and copying
• Accessible to all staff

Level 3: Restricted areas

• Finance department
• HR office with personnel files
• IT rooms with network equipment
• Archives and storerooms
• Accessible only to specific departments

Level 4: High-security areas

• Server rooms and data centres
• Laboratories with sensitive equipment
• CEO and senior management offices
• Secure rooms and vaults
• Often require two-factor authentication

A good digital locking system lets you define these zones and assign each employee the right access level based on their role and duties. You can also set time restrictions so that certain people only have access during office hours.

Integration with other systems

For businesses, it is valuable if the access control system can be integrated with other systems.

HR systems

Automatic provisioning and deprovisioning of access. When someone is hired, they automatically receive the right access rights based on their role. When someone leaves, all access is revoked immediately.

Time and attendance

Use entry logs as the basis for attendance records. The system can automatically log when employees arrive and leave, simplifying payroll and scheduling.

Visitor management systems

Digital visitor passes are activated automatically when a guest checks in at reception. The visitor is given limited access to specific areas for a predetermined period.

Fire alarm and evacuation systems

Electric strikes on escape routes are released automatically in the event of a fire so that staff can get out. The system can also show where people are in the building to assist the emergency services.

Video surveillance (CCTV)

Link entry logs with video surveillance for full traceability. In the event of an incident, you can see both who passed through and what happened on video.

Building management

Integrate with climate control, lighting and ventilation. When the first person arrives in the morning, heating and lighting are switched on. When the last person leaves in the evening, energy consumption is reduced.

How to scale the system

Businesses grow and change. Your digital locking system must be able to grow with the organisation.

What to consider:

The ability to add more doors without replacing the central system. An unlimited number of users or a high limit. Modular design that lets you upgrade parts without replacing everything. Open APIs for integration with future systems. A cloud-based platform that scales automatically. Support for multiple buildings and geographical locations. A flexible licensing model that grows with your needs.

Regulatory compliance

Some sectors have specific requirements for access control and logging.

Healthcare

GDPR and patient data legislation set strict requirements. You must be able to trace exactly who has had access to sensitive patient areas and when. Logs must be retained as required by law, but also deleted when they are no longer needed.

Finance

Banking confidentiality rules and requirements for two-factor authentication for vaults and secure areas. Audits often require detailed documentation of all access events.

Industry

Protection of patents and confidential product information. Export-controlled technology may require additional security levels and documentation of who has had access.

Public sector

Freedom of information rules may mean that logs must be disclosed on request, while personal data must still be protected under GDPR.

Make sure your access control system meets industry-specific standards and can provide the documentation required for audits.

Costs of digital locking systems

Costs vary considerably depending on the system, the number of doors and the features required.

Initial costs

Hardware

Installation

• Electrician and locksmith: typically priced per door
• Network cabling: priced per connection point
• Configuration and programming: charged by the hour
• Staff training: one-off cost

Software

• Perpetual licence: depends on system size
• Cloud-based solution: monthly fee per door
• Mobile app: Often included
• Integrations: priced per integration

Ongoing costs

Monthly fees for cloud-based systems:

• Small systems (1–10 doors): low monthly fee
• Medium-sized systems (11–50 doors): moderate monthly fee
• Large systems (50+ doors): higher monthly fee

Annual maintenance:

• Service agreement: 5–10% of hardware cost
• Security updates: Often included
• Support and helpdesk: annual fee
• Battery replacement (for battery-powered locks): small annual cost per lock

Examples of total cost

Residential building with 30 flats

Initial investment:

• 5 digital locking systems with electric strikes
• RFID readers and mobile support
• Installation and configuration
• Software and licences
• Total: the sum of the items above

Ongoing costs:

• Support and licences: monthly subscription
• Maintenance and servicing: annual cost
• Total per year: support, licences and maintenance combined

Annual savings:

• Key management and copying
• Lock changes at move-out
• Administration time (estimated value)
• Total savings: more than twice the annual running costs

Net result after savings: Investment paid back in about 2.5 years

Company with 50 employees

Initial investment:

• 20 doors with RFID and biometrics: the largest single cost item
• Central units and network
• Installation and integration: the second-largest cost item
• HR system integration
• Training
• Total: the sum of the items above

Ongoing costs:

• Support and licences: monthly subscription
• Maintenance: annual cost
• Total per year: support, licences and maintenance combined

Choosing the right digital locking system

Here are the factors to consider before investing in an access control system.

Map your needs

Start by answering these questions:

• How many doors will the system cover?
• How many users need access?
• Which access levels and zones are needed?
• Is integration with other systems required (HR, time and attendance, fire alarm)?
• What security requirements apply to the organisation?
• Does the system need to work offline?
• Are there specific compliance requirements?

Evaluate the technology

Basic technology choices:

Test the user experience

How quickly does the door open after identification? Is the system intuitive for new users? Is the mobile app easy to navigate and logical? How many steps does it take to let a visitor in? Does the system work equally well for all age groups? Is there clear feedback when something goes wrong? How easy is it to change phones? Can the system be used with gloves on (relevant outdoors)?

Security and support

What security certifications does the supplier hold? ISO 27001 and SOC 2 are good standards to look for. How often is the system updated with security patches? Which encryption standard is used? At least AES-256 is recommended. Are penetration tests documented? How are security incidents handled? What happens in the event of a power cut or system failure? How quickly can support be reached? Is local support available in your language? What warranty period is offered?

Future-proofing

A digital locking system is a long-term investment. Consider the following:

Can the system grow with the organisation without a complete overhaul? Does the system use open standards or proprietary protocols? Is there an active ecosystem of partners and developers? How long has the supplier been on the market? What are the supplier's plans for the future? Can the system be updated with new features later?

Cost versus value

Do not just compare the purchase price; compare the total cost of ownership (TCO) over 5–10 years.

Include in the TCO calculation:

Initial hardware and installation. Ongoing licences and support. Maintenance and updates. Energy consumption. Administration time. Training of new users. Any future expansion.

Weigh against:

Savings from reduced key administration. Improved security and reduced risk of break-ins. Time savings for tenants and employees. Opportunities for new services and revenue. Increased property value.

Legal and compliance

Does the system comply with GDPR and local regulations on video surveillance? How long is log data kept? Who has access to the logs? How are users informed about data processing? Are there procedures for data breaches? Do you have a data processing agreement with the supplier? Is all access to the system's administration documented?

The future of digital locking systems and access control

Access control and digital locking systems are developing rapidly. Here are some of the trends shaping the future.

Greater standardisation

Today, many systems are proprietary, which means you are locked in to one supplier. But the industry is moving towards more open standards such as:

• Open Supervised Device Protocol (OSDP) for secure communication between readers and controllers
• Bluetooth mesh for large-scale installations
• Matter for smart home integration
• API standards for easier integration

This makes it easier to switch suppliers and integrate different systems with each other without major costs.

Biometrics are becoming cheaper and better

Prices for biometric readers continue to fall while accuracy improves. Technologies that are becoming increasingly common:

• Multimodal biometrics (combining facial recognition and fingerprint)
• Iris scanning for extremely high security
• Vein scanning that works even with gloves on
• Gait recognition that identifies people at a distance

Within a few years, biometrics will be standard even in smaller properties and businesses.

AI-driven security

Machine learning will make access control systems smarter by learning the normal patterns of each user. The system can detect anomalous behaviour automatically and anticipate security risks before they occur. Access rights can be optimised based on actual usage, and inefficient security routines can be identified.

If an employee has never used their access to the server room, the system can suggest that the access right be removed. If someone suddenly tries to get in in the middle of the night, it is flagged automatically.

Sustainability and energy efficiency

Suppliers are starting to offer greener alternatives with lower energy consumption thanks to better battery technology. Recyclable materials in the hardware and longer service life through modular design are becoming more important. Solar-powered readers for outdoor use and carbon-offset transport and production are on the rise.

Modern digital locking systems can also be integrated with the building's energy management to automatically adjust heating, ventilation and lighting based on when people pass through.

Greater interoperability between systems

The vision for the future is a mobile key that works seamlessly everywhere. At home in your flat, at the office where you work, in the car park beneath the office, at the gym you belong to, on public transport and in hotels when you travel. All in the same app with a single shared digital identity.

Summary

Digital locking systems and modern access control offer tremendous convenience, flexibility and improved security compared with traditional mechanical locks. For both residential buildings and businesses, there are clear benefits in terms of administration, cost savings and ease of use.

Key benefits of digital access control:

• No more physical keys and key management
• Flexible access rights management with different access levels
• Complete logging of all entries
• Easy onboarding of new users
• Cost savings over time
• Remote management and integration options

Challenges to manage:

• Cyber security requires active management
• Data protection in line with GDPR must be implemented
• Dependence on power and internet requires backup solutions
• The initial investment can be significant
• Users need training and support

Key components of a complete system:

Readers (RFID, mobile, biometric) are combined with electric strikes that have the right holding force and fail-safe function. Controllers and central units run the system, while software handles administration and logging. Network infrastructure or wireless communication links the components, and backup solutions keep the system running during power cuts.

For most modern properties and businesses, the question is no longer whether to switch to digital access control, but when – and which system suits them best. With the right preparation and a well-considered choice, you get a locking system that works smoothly for many years to come and can easily be adapted as your needs change.

Technology is developing quickly, and the systems of the future will be even smarter, more secure and easier to use. By choosing systems with open standards and good scalability, you ensure that your investment holds its value as new innovations arrive. Electric strikes and other components are continuously being developed to become more energy-efficient and environmentally friendly, while security keeps improving.