A commercial intercom system with door release is a building entry system that combines two-way audio or video communication with an electronically controlled door lock. When a visitor arrives, a tenant or staff member receives the call, verifies the visitor, and triggers a remote unlock signal that briefly disengages the door lock, allowing entry without physical keys or a front desk presence.
TL;DR: These systems connect an intercom panel to an electronic lock (typically an electric strike or magnetic lock) via a relay. When the unlock signal is triggered, the relay either cuts power to the lock mechanism or applies power to it for a few seconds.
Cloud-based systems route calls and door release through mobile apps or computers. Choosing the right setup depends on your door type, power configuration, and whether the lock needs to be a fail-safe or a fail-secure during a power outage.
Looking for something more specific? This guide focuses on door release hardware, wiring, and installation considerations for commercial buildings. If you need a broader overview of commercial intercom options, see our guide to commercial intercom systems. If you are evaluating video-specific setups, see our video intercom systems with door release guide.
How We Built This Guide
- Drawing on Swiftlane’s experience deploying commercial intercom and access control systems across office buildings, mixed-use properties, and multi-entrance commercial sites
- Informed by conversations with property managers and facilities teams about the wiring, hardware, and installation decisions that come up most in real projects
- Supplemented with reference to NFPA 101, NIST physical access control guidelines, and Security Industry Association recommendations cited throughout
Key Takeaways
- A commercial intercom system with door release allows staff or tenants to verify visitors and unlock doors remotely
- Electric strikes and magnetic locks are the most common door release mechanisms, each suited to different door types
- Cloud-based systems enable door release from mobile devices or computers, replacing fixed desk stations
- The biggest factor in performance isn’t features but whether the system is properly matched to your building’s hardware and infrastructure
Table of Contents
- What Is a Commercial Intercom System With Door Release?
- How These Systems Work
- Door Release Mechanisms
- Electric Strike vs Magnetic Lock
- Why Smart Locks Are Gaining Traction
- How Door Release Wiring Works
- Fail-Safe vs. Fail-Secure: What It Means in Practice
- Key Features in Commercial Intercom Systems
- Infrastructure and Installation Considerations
- Installer Preflight Checklist
- Common Failure Modes and Fixes
- Security and Access Control Considerations
- How Swiftlane Supports Commercial Buildings
- Choosing the Right System
- FAQs
What Is a Commercial Intercom System With Door Release?
A commercial intercom system with door release allows building staff or tenants to communicate with visitors at the entrance and unlock the door remotely once access is approved.
Today, many systems also integrate with broader access control platforms, enabling property managers to manage entry across multiple doors and for multiple users from a single interface. These integrations can include smart locks, mobile credentials, and centralized dashboards that unify intercom and access control workflows.
For example, platforms like Brivo and Swiftlane support cloud-based management, remote access permissions, and real-time activity logs, making it easier to monitor entry, adjust access, and maintain visibility across the building.
How These Systems Work
Here’s how the process typically works in a commercial building:
1. Visitor initiates a call: A visitor arrives at the building entrance and uses the panel to select a tenant, office, or reception desk from the directory.
2. The call is received: The tenant or staff member receives the call on a desk station, smartphone, computer, or mobile app, depending on the system.
3. Verification happens: Staff can speak with the visitor through the intercom. With video intercom systems, visitors can also be seen on camera for added security.
4. Door release is triggered: If access is approved, the authorized user presses the unlock button on their device. This signals the electronic locking mechanism connected to the door.
5. The door unlocks temporarily: The door release mechanism disengages the lock for a few seconds, allowing the visitor to enter, then automatically relocks.
In modern commercial buildings, this process can be handled entirely via mobile devices or cloud-based systems, allowing staff to grant access remotely. Many systems also log entry activity for visibility and security.
However, how the door actually unlocks depends on the type of release mechanism behind the system.
Door Release Mechanisms
For an intercom system to unlock a door remotely, it must connect to an electronic locking mechanism installed at the entrance. The type of lock used can affect how the door release works, how secure the entry point is, and how easy the system is to install.
In commercial buildings, two types of electronic locks are most commonly used with intercom systems.
Electric Strike
An electric strike replaces the fixed strike plate on the door frame. When the intercom system sends the unlock signal, the strike plate temporarily releases the latch, allowing the door to be opened.
Electric strikes are widely used in office buildings and commercial properties because they work well with many existing door setups.
They are often preferred for:
- Metal or wood doors
- Retrofit installations
- Buildings with traditional tech hardware
Electric strikes are typically fail-secure, meaning the door remains locked during a power outage unless backup power is installed.
Magnetic Lock (Maglock)
A magnetic lock, often called a maglock, uses a strong electromagnet installed at the top of the door frame. When power is applied, the magnet holds the door closed. When the intercom triggers the door release, power to the magnet is temporarily cut so the door can open.
Maglocks are often used in:
- Glass door entrances
- High-traffic commercial buildings
- Modern office spaces
These locks are usually fail-safe, meaning the door unlocks automatically during a power outage to comply with safety regulations.
Electric Strike vs Magnetic Lock
| Feature | Electric Strike | Magnetic Lock (Maglock) |
| How it works | Releases latch when triggered | Cuts power to the magnet to release the door |
| Installation | Replaces strike plate (minimal door changes) | Mounted on door frame (surface installation) |
| Best for | Retrofit projects, traditional doors (wood/metal) | Glass doors, high-traffic entry points |
| Power behavior | Fail-secure (stays locked during outage) | Fail-safe (unlocks door during outage) |
| Security use case | Fail-secure; compatible with egress paths when paired with free mechanical egress hardware | Fail-safe with fire alarm release; standard approach for life-safety compliance on egress paths |
| Aesthetics | More discreet, integrated into the door frame | Visible hardware on door/frame |
Both options are widely used in commercial buildings, but the right choice depends on your door type, safety requirements, and how the space is used day-to-day.
Why Smart Locks Are Gaining Traction
While electric strikes and maglocks remain common, many modern buildings are shifting toward smart lock integrations. These systems reduce reliance on door-specific hardware decisions and enable digital access management via mobile credentials, PINs, or cloud-based platforms.
How Door Release Wiring Works
For the intercom to trigger a door unlock, the panel must send a signal to the electronic lock through a relay output. Understanding how that relay is wired helps avoid the most common installation mistakes and ensures the lock behaves correctly under normal and fault conditions.
Relay Output: NO vs. NC
Most commercial intercom panels include a built-in relay with two wiring configurations.
Normally Open (NO): The circuit is open (no power flowing) at rest. When the door release is triggered, the relay closes, completing the circuit and powering the lock. This configuration is standard for electric strikes.
Normally Closed (NC): The circuit is closed (power flowing) at rest. When the door release is triggered, the relay opens, cutting power to the lock. This configuration is standard for magnetic locks, which require continuous power to stay engaged.
Wiring the relay to the wrong terminal (NO vs. NC) is one of the most common reasons a newly installed door release either fails to unlock or stays unlocked permanently.
Dry Contact vs. Wet Contact
Dry contact: The relay provides a switch only, with no voltage. The installer supplies the lock with separate power from a dedicated power supply. This is the most common setup in commercial installations and gives the installer full control over lock voltage and current.
Wet contact: The relay provides both the switch and a voltage output (typically 12V DC). This simplifies wiring in smaller or simpler setups but offers less flexibility for higher-draw locks.
Most commercial-grade electric strikes and maglocks require a dedicated lock power supply, regardless of contact type, particularly in multi-door installations where load management is critical.
Lock Power Supply
Electronic door locks in commercial buildings typically operate at either 12V DC or 24V DC. The correct voltage depends on the lock manufacturer’s specifications.
A few practical notes:
- Undersupplying voltage is a common cause of weak or inconsistent lock holding force
- The power supply should be sized to handle the total current draw across all locks on the circuit, plus a buffer
- In installations where backup power is required, the lock power supply should connect to a UPS or battery backup, not just the intercom panel
Where the Intercom Fits In
The intercom panel itself does not typically power the lock. It sends a low-voltage signal to the relay, which then controls the separate lock power circuit. This means two independent power sources are usually involved: one for the intercom panel and one for the door hardware.
Keeping these circuits separate also makes troubleshooting easier. If the door fails to release, the fault can be isolated to either the intercom signal path or the lock power circuit, rather than diagnosing both together.
Fail-Safe vs. Fail-Secure: What It Means in Practice
Every electronic lock in a commercial building has a default behavior when power is lost. That behavior, either holding the door locked or releasing it, is not just a product specification. In many buildings, it is a code requirement.
What the Terms Mean
Fail-safe: The lock releases and the door opens freely when power is lost. Magnetic locks are fail-safe by design, because they require continuous power to stay engaged. When power cuts, the magnet releases.
Fail-secure: The lock stays locked when power is lost. Electric strikes are typically fail-secure, meaning the latch remains held even during an outage. Access requires a physical key or manual override.
Why It Matters Beyond the Spec Sheet
The distinction becomes critical in two scenarios: fire alarms and power outages.
Fire alarm integration: Most commercial buildings are required to connect electronically locked doors to the fire alarm system. When the alarm triggers, fail-safe locks release automatically to allow egress. This is a life-safety requirement in most jurisdictions and is typically enforced under NFPA 101 (the Life Safety Code) and local fire codes. Fail-secure locks on egress paths require additional hardware, such as a fire alarm relay or a listed electrified panic device, to meet this requirement.
Power outages: A fail-secure lock keeps the building secured during an outage, which is preferable for security-sensitive entry points. A fail-safe lock prioritizes occupant egress over security. The right choice depends on whether the door is a primary egress path, a secured interior door, or a perimeter entry point.
Practical Decision Guide
| Door type | Typical hardware | Recommended lock mode | Reason |
| Primary building entrance (egress path) | Electric strike or electrified exit device | Fail-secure, with free mechanical egress | Free egress hardware allows exit regardless of power; fail-secure keeps entry controlled |
| Interior secured door (non-egress) | Electric strike | Fail-secure | Maintains security during an outage; no egress requirement to satisfy |
| Stairwell door | Electric strike/ electrified lever | Fail-secure (positively latched) | Fire-rated doors must stay latched to hold their rating; fail-safe here voids the rating |
| Parking garage entry | Electric Strike or maglock | Fail-secure or fail-safe | Depends on hardware installed and local code, not on egress status alone |
| Glass lobby door (high traffic) | Maglock | Fail-safe | Maglocks fully de-energize on release, so egress requires alarm tie-in and REX, not just fail-safe mode |
A Note on Backup Power
Neither fail-safe nor fail-secure eliminates the need for backup power planning. A fail-secure lock that loses power keeps the door locked, but the intercom panel may go offline, leaving no way to grant access remotely. A fail-safe lock that loses power opens the door, which may be acceptable for egress but creates a security gap.
Most commercial installations address this with an uninterruptible power supply (UPS) connected to both the intercom panel and the lock power supply, keeping the full system operational during short outages and allowing a controlled shutdown during extended ones.
When specifying a system, confirm with your installer which components are covered by backup power and for how long.
Key Features in Commercial Intercom Systems
Not all commercial intercom systems offer the same capabilities.
When evaluating options, property managers and building operators should consider how the system will perform in real-world building operations, from visitor management to long-term scalability.
The table below highlights the most important features to consider when choosing a commercial intercom system with door release.
| Feature | Why It Matters | Ask Your Vendor |
| Video Capability | Allows staff to visually verify visitors before unlocking the door | What is the video quality in low-light conditions, and is the video stored or live-only? |
| Remote Door Release | Lets authorized users unlock the door from inside the building | Can users unlock doors remotely via mobile or desktop, and are there role-based permission controls? |
| Mobile Access | Enables tenants to receive calls and unlock doors from their phones | Does the system support both iOS and Android, and can multiple users manage access per unit or office? |
| Directory Management | Helps visitors quickly find the right tenant or office | How is the directory updated, and can tenants manage their own listings? |
| Access Logs and Activity Tracking | Records entry activity for monitoring and security | Can logs be exported to external systems (e.g., SIEM) and how long is data retained? |
| Access Control Integrations | Allows the intercom to work with keycards or mobile credentials | Which access control systems does it integrate with, and is it native or via API? |
| Scalability | Supports additional entrances or tenants as the building grows | Can the same dashboard manage 10+ entry points across multiple buildings? |
| Installation Flexibility | Helps systems adapt to different building layouts | Does it support PoE (Power over Ethernet) for installation without running separate power lines? |
Infrastructure and Installation Considerations
Before installing a commercial intercom system, evaluating your building’s existing doors, wiring, and network connectivity helps avoid compatibility issues and unnecessary upgrades.
Door Hardware Compatibility
The first consideration is whether the building’s doors can support an electronic locking mechanism such as an electric strike or magnetic lock, which helps determine which door release mechanism will work best.
Wiring and Power Requirements
Traditional intercom systems often require extensive wiring between the entry panel, indoor stations, and door hardware. This can make installation more complex in older buildings.
Many modern systems use IP-based or cloud-connected technology, which can reduce wiring requirements and make retrofits easier. However, reliable power and network connectivity are still essential.
Network Connectivity
Cloud-based intercom systems rely on internet connectivity to route calls, support mobile access, and store activity logs.
Before installing the system, building managers should confirm that the entrance location has:
- Stable internet connectivity
- Sufficient network bandwidth
- Secure network configuration
This helps ensure consistent system performance.
Retrofitting an Existing Building
Many commercial projects involve replacing legacy intercom or access systems rather than installing from scratch. In these cases, assessing existing infrastructure up front can prevent delays and additional costs.
Key things to check include:
- Wiring type and gauge: Can existing cabling support IP or PoE systems, or will new runs be required?
- Panel voltage and power supply: Does the current setup meet the requirements of modern intercom hardware?
- Existing door hardware: Are the current locks compatible with electric strikes or maglocks, or will door modifications be needed?
Clarifying these early helps determine whether the upgrade can reuse existing infrastructure or requires partial reconfiguration.
Multi-Entrance Planning
Many commercial properties have multiple access points, including:
- Main lobby entrances
- Side entrances
- Parking garage doors
- Service entrances
When planning the installation, it’s helpful to determine whether the intercom system will manage a single entrance or multiple entry points throughout the building.
A scalable system makes it easier to expand access control later as building needs evolve.
Installer Preflight Checklist
Before any commercial intercom and door release system goes live, verifying the following items catches the most common installation failures before they become callbacks. This checklist applies to both new installations and retrofit projects.
Door Hardware
- Confirm the door type (wood, metal, glass, hollow metal frame) and match it to the appropriate lock mechanism (electric strike or maglock)
- Verify the door frame can accommodate the chosen lock without structural modification
- Check that the door closes and latches consistently without manual adjustment. Electronic locks will not compensate for a misaligned door
- Confirm whether the door is on an egress path and identify the required lock mode (fail-safe or fail-secure) before ordering hardware
- If replacing existing hardware, verify the new lock’s mounting dimensions match the cutout or surface area available
Wiring and Power
- Identify the relay output type on the intercom panel (NO or NC) and confirm it matches the wiring configuration required by the lock
- Measure the distance between the intercom panel and the lock. Voltage drop over long cable runs can cause unreliable lock behavior, particularly at 12V DC
- Confirm the lock power supply voltage matches the lock specification (12V or 24V DC) and that the supply is sized for the total current draw across all connected locks
- Check whether existing conduit or cable runs can be reused, or whether new runs are required
- Confirm backup power coverage. Identify which components (intercom panel, lock power supply, network switch) are on UPS and for how long
Network and Connectivity
- Confirm stable internet connectivity at the entry panel location before installation, not after
- Verify the network switch at the entry point supports PoE if the intercom panel is PoE-powered
- Check that the entry panel location is on a secure network segment, separate from general tenant or guest Wi-Fi
- Confirm sufficient upload bandwidth for video streaming if the system includes video intercom capability
- Test network connectivity at the physical panel mounting location, not just at the nearest network closet
Fire and Safety Compliance
- Confirm whether the door requires fire alarm integration and, if so, verify the lock release is wired to the fire alarm control panel output
- Check local AHJ (Authority Having Jurisdiction) requirements for electronically locked egress doors before finalizing hardware selection
- Verify that request-to-exit (REX) devices are specified for any door where occupants need to exit without triggering the intercom
- Confirm that all egress doors have a mechanical override or listed free-egress hardware in place
System Configuration
- Test the relay output signal from the intercom panel before connecting the lock, using a multimeter to confirm the relay opens and closes correctly on trigger
- Confirm door release timing (how many seconds the lock disengages) is set appropriately for the door’s traffic volume
- Verify that access permissions are configured and that only authorized users have door release capability before the system goes live
- Test the full visitor flow end to end: visitor initiates call, staff receives call, staff triggers door release, door unlocks and relocks correctly
- Confirm activity logging is active and entries are being recorded before handing the system over to the property manager
Common Failure Modes and Fixes
Even properly installed systems run into issues. The table below covers the most frequently reported problems with commercial intercom and door release setups, along with the most likely causes and first steps for resolving them.
| Symptom | Most Likely Cause | First Step |
| Door does not release | Relay wired to wrong terminal (NO vs. NC) or lock power supply off | Test relay output with a multimeter. Confirm power supply voltage |
| Door stays unlocked | Relay stuck closed, or NO/NC wiring reversed | Check terminal wiring. Power cycle the panel |
| Intermittent release | Voltage drop on long cable run or loose wire connection | Measure voltage at lock terminals under load. Check all terminations |
| Call not received | App notifications disabled or user not provisioned correctly | Check app permissions and confirm user setup in the dashboard |
| Video black or pixelated | Insufficient bandwidth or camera lens obstructed | Run a bandwidth test at the panel. Clean the lens |
| Relocks too quickly | Door release timer set too short | Adjust relay hold time in the dashboard (standard range: 3 to 10 seconds) |
| System offline during outage | Panel or network switch not on UPS | Add UPS coverage to the panel and network switch |
| Fire alarm does not release door | Lock not wired to fire alarm control panel output | Confirm fire alarm relay wiring and test with a test alarm trigger |
Security and Access Control Considerations
A commercial intercom system with door release directly controls access at your building’s entry points.
In practice, the most secure setups combine intercom functionality with structured access control, clear permission levels, and reliable audit trails, so every entry event is both intentional and traceable.
Below are several security considerations property managers should keep in mind.
Visitor Verification
Video-enabled intercom systems allow staff to both speak with and visually confirm visitors before unlocking the door, an approach the Security Industry Association highlights as an important component of modern access control strategies.
Controlled Door Release Permissions
Not every user in a building should be able to unlock entrance doors. Many modern intercom systems allow administrators to assign door release permissions only to authorized staff or tenants.
This helps prevent accidental door releases and ensures that access decisions remain consistent with the building’s security policies.
Access Activity Logs
Many commercial intercom and access control systems record door release activity, including when the door was unlocked and which user triggered the release.
Maintaining access logs helps property managers monitor entry activity and investigate potential security concerns if they arise. The National Institute of Standards and Technology recommends maintaining physical access audit logs at entry and exit points to monitor facility access and review activity during security incidents.
How Swiftlane Supports Commercial Buildings
Swiftlane is a cloud-based intercom and access control platform that goes beyond basic visitor entry. Instead of relying on traditional desk phones or indoor stations, tenants and staff receive intercom calls and release doors directly from their smartphones.
From a centralized dashboard, property managers can manage access permissions, monitor entry activity, and update tenant directories across multiple entrances, making it easier to scale as the building grows.
The platform is commonly used in commercial office buildings, mixed-use properties, and other environments where secure visitor verification and flexible remote access are both priorities.
Choosing the Right System
Commercial intercom systems with door release have become an essential tool for managing building entry, allowing staff and tenants to verify visitors, unlock doors remotely, and maintain better control over who enters the building.
Selecting the right system means understanding how the technology fits your building’s daily operations, from door hardware and installation to security best practices. Evaluating your infrastructure, visitor traffic, and access control needs will help you find a solution that works for your tenants, staff, and guests.
FAQs
How much does a commercial intercom system with door release cost?
Costs vary depending on building size, system type, and installation complexity, but most commercial intercom systems fall into these general ranges:
- Small setups (single or few doors): $1,000 to $5,000+
- Mid-size commercial buildings: $5,000 to $20,000+
- Large or multi-entrance properties: $20,000 to $50,000+
Key cost drivers include the number of entry points, type of door hardware (electric strike vs maglock), wiring or retrofit requirements, and whether the system is cloud-based with ongoing software fees.
For most buyers, the biggest cost variable isn’t the intercom itself, but the installation and infrastructure needed to support it.
Can a commercial intercom system unlock the door remotely?
Yes. Most modern commercial intercom systems allow authorized users to unlock doors remotely using a desk station, mobile app, or computer. Once the visitor is verified via an intercom call, the user can trigger the door release, temporarily disengaging the electronic lock to allow the visitor to enter.
What happens if the power goes out — does the door stay locked or unlocked?
It depends on the type of electronic lock installed. Fail-secure locks remain locked during a power outage, keeping the building secured but requiring manual access in an emergency. Fail-safe locks release and allow the door to open freely when power is lost, a common occurrence in buildings where emergency egress is a priority.
Most commercial installations also include a backup power source, such as a battery or UPS, to keep the intercom and door release system running during short outages. The right configuration depends on your building’s security requirements and local fire and safety codes.
Do commercial intercom systems work with existing door hardware?
In many cases, yes. Most commercial intercom systems are designed to integrate with common door hardware, including electric strikes, magnetic locks, and electrified exit devices. However, compatibility depends on the age and condition of your existing hardware, the wiring available at the door, and whether the lock mechanism supports remote release.
If your building already has electronic door hardware, a new intercom system can often be connected without major upgrades. Older mechanical locks must be replaced with an electronic alternative before an intercom door release can be added.
