Construction’s cybersecurity frontier in the age of smart buildings
Beneath the surface and increasingly embedded within the very fabric of our infrastructure, lies a complex nervous system of interconnected technologies. These are "smart buildings" with automated HVAC and lighting to integrated security and access control, the Internet of Things (IoT) and sophisticated Building Management Systems (BMS). However, with this remarkable integration comes a new, pervasive threat - a cybersecurity risk – and it brings with it, the potential of major problems in the future, writes John Ridgeway.
As buildings become more integrated and 'smart,' they also become larger, more enticing targets for cybercriminals. The consequences of a breach extend far beyond data loss - they can compromise operational integrity, occupant safety and critical national infrastructure. This new frontier demands a proactive approach, especially during the construction phase, where vulnerabilities can be inadvertently baked into the very foundations of these intelligent structures.
Smart buildings are complex cyber-physical systems, intertwining Information Technology (IT) with Operational Technology (OT). This convergence significantly expands the attack surface, creating numerous entry points for malicious actors. Every smart sensor, camera, smart lock and connected appliance is a potential endpoint. Many IoT devices are designed for convenience, not security, often shipping with weak default passwords, unpatched firmware and limited security features. A single compromised thermostat could be a gateway to the entire building network.
HVAC, lighting, elevators, fire suppression, access control and energy management systems were once isolated. Now, they're often networked, creating a single point of failure. A breach in one system (e.g., an HVAC control) could cascade, impacting other critical operational systems or even gaining access to the broader corporate IT network.
Many smart buildings also incorporate older, less secure operational technology that was never designed for internet connectivity. The "if it isn't broken, don't fix it" mentality often leads to unpatched vulnerabilities that cybercriminals actively seek to exploit. Regular updates are often difficult to implement on OT systems due to concerns about operational disruption.
Furthermore, smart building networks are flat, meaning that once an attacker gains access to one device, they can move laterally across the entire network, potentially infiltrating critical systems. Shared administrative credentials, easily guessable passwords and a lack of multi-factor authentication (MFA) or role-based access control (RBAC) also create open doors for unauthorised access.
Third-party and supply chain risks
Smart buildings rely on a vast ecosystem of vendors, contractors and service providers. Each third party introduces potential vulnerabilities. A compromised supplier's software update or remote access credentials could be a conduit for attack. The construction supply chain itself is a prime target for phishing, ransomware and data breaches. In addition, smart buildings collect a wealth of sensitive data such as occupant movement patterns, energy usage, security camera feeds and even personal information from integrated occupant apps. If unencrypted or poorly protected, this data is vulnerable to interception, theft, or manipulation.
The ability to manage building systems remotely is a key benefit, but also a significant security risk if not properly secured with virtual private networks (VPNs) or Zero Trust Network Access (ZTNA).
A successful cyberattack on a smart building can have devastating consequences. HVAC systems can be shut down, lights disabled, elevators jammed, or fire alarms manipulated, leading to discomfort, significant downtime and financial losses. Unauthorised access to security cameras, door locks, or fire suppression systems could also endanger occupants.
Sensitive tenant data, operational patterns and even intellectual property (blueprints, proprietary designs) can be exfiltrated, leading to regulatory fines, reputational damage and competitive disadvantage. Furthermore, attackers can encrypt building data or disable critical systems, demanding a ransom.
A high-profile breach can also severely damage a building owner's or developer's reputation, leading to loss of tenant confidence, decreased property value and difficulty attracting future clients.
Addressing cybersecurity during construction
The conventional wisdom of "fix it later" simply doesn't apply to smart building cybersecurity. Retrofitting security measures is far more costly and less effective than designing them in from the outset. A 2024 study by IBM found that addressing security vulnerabilities during the design phase costs six times less than patching them post-deployment. This necessitates a fundamental shift in mindset within the construction industry, elevating cybersecurity from an afterthought to a foundational pillar of every project phase.

Cybersecurity experts must be brought into the project from the very master-planning and conceptual stages, alongside architects, engineers and sustainability consultants. They help identify potential digital risks, define security requirements and set standards for secure integration before the first brick is laid.
Fostering collaboration between IT, OT, and construction teams is also crucial. Historically siloed, these departments must now work together to understand interdependent systems and data flows, ensuring security measures are applied consistently across the entire smart building ecosystem.
Contractors must rigorously vet all technology vendors and suppliers. This includes assessing their cybersecurity posture, demanding secure product development lifecycles and ensuring contractual agreements include stringent cybersecurity clauses. There is also the need to prioritise IoT devices and BMS components designed with security in mind, featuring strong encryption, secure boot processes and regular firmware updates. Avoid devices with known vulnerabilities or weak default settings.
All this means that contractors must design the network with strong segmentation, isolating critical OT systems (HVAC, elevators) from less secure IT networks (guest Wi-Fi, general office networks). This minimises lateral movement of attackers if one segment is compromised. Implement DMZs for devices that interact with external systems, providing an additional layer of security and move away from outdated Layer 2 VLAN configurations to more secure Layer 3 network architecture where possible, enhancing isolation.
Secure configuration
As an added precaution, mandate immediate change of all default passwords for all devices and systems upon installation. Configure access controls to grant users and devices only the minimum necessary permissions to perform their functions (Role-Based Access Control - RBAC). Close any unnecessary ports or services on devices and networks that are not essential for operations. Implement end-to-end encryption for all data at rest and in transit, especially for sensitive information collected by building systems. Secure communication channels with VPNs and TLS encryption and conduct thorough security configuration reviews during deployment to ensure all features are enabled and correctly configured.
Only collect and store data that is absolutely necessary for the building's operation. Classify sensitive data and apply appropriate security controls (encryption, access restrictions) based on its criticality and ensure data stored within smart building systems and associated cloud infrastructure is encrypted and protected by robust security measures.
Furthermore, as digital twins become integral to construction and operation, ensuring the security of the vast amounts of real-time data flowing into and out of these virtual replicas is paramount. Data integrity and access controls for digital twins are critical.
Without doubt, the proliferation of smart buildings marks an exciting evolution in architecture and urban planning. However, this evolution comes with an undeniable imperative to prioritise cybersecurity from the earliest stages of construction. The traditional "build and hand over" mindset must give way to a "secure by design, secure for life" philosophy.
By embracing early collaboration, robust procurement, meticulous network design, continuous monitoring and comprehensive training, the construction industry can transform smart buildings from potential cyber liabilities into resilient, secure, and truly intelligent assets. The future of our built environment depends not just on how smart our buildings are, but on how securely they operate. The challenge is significant, but by integrating cybersecurity as a core discipline throughout the construction lifecycle, we can ensure that our increasingly connected habitats are not only efficient and comfortable, but also truly safe and secure against the digital threats of tomorrow.
Additional Blogs

Constructing resilience in the world’s most extreme cold climates
Building in the Arctic and other extreme cold climates presents some of the most formidable challenges in construction, demanding an unparalleled blend of specialised knowledge, innovative materials...
Read morerising price of copper and its implications for the UK electrical market
Copper has long been an essential material in the electrical and construction industries. Its excellent conductivity, corrosion resistance and ductility make it ideal for wiring, power generation and...
Read more

Six years after Beechmere the fire safety gap remains
The fire that tore through Beechmere Retirement Village in Crewe in August 2019 remains one of the most devastating fire incidents involving vulnerable people in the UK in recent memory. The...
Read more