Private 5G is arriving in UK commercial buildings
Private 5G networks, dedicated cellular infrastructure serving a single site or organisation, have been deployed in UK manufacturing, logistics and campus environments for several years. In 2025 and 2026, they are beginning to appear in commercial office buildings, particularly in the City of London, Canary Wharf and large mixed-use developments across the South East. The driving factors are the limitations of enterprise WiFi in high-density environments, the growing need for deterministic low-latency connectivity for real-time AI applications, and the availability of OFCOM-licensed spectrum that allows organisations to deploy private 5G without sharing spectrum with public operators.
Understanding what private 5G actually requires from the building’s cabling infrastructure, and how it relates to existing WiFi and structured cabling systems, is essential for any IT Director or Facilities Manager considering a private 5G project.
How in-building 5G works: DAS and small cells
In-building 5G coverage is typically delivered by one of two mechanisms: a distributed antenna system (DAS) or small cells. A DAS uses a central head-end unit, connected by fibre optic cabling to remote antenna units (RAUs) distributed around the building. The head-end amplifies the 5G signal and distributes it to each RAU, which radiates it into the local area. Small cells are self-contained 5G base stations, physically smaller than a traditional macrocell, that are connected by Cat6A or fibre to the building’s network and provide coverage in their immediate vicinity.
Both approaches require structured cabling infrastructure. A DAS requires fibre optic backbone cabling between the head-end and each RAU, plus Cat6A or fibre for management and power connections. Small cells require Cat6A cabling for data connectivity and, in most cases, PoE++ for power delivery, a single 5G small cell can draw 30 to 60W depending on the technology tier and the number of active antennas.
The question is not whether private 5G needs structured cabling. It does. The question is whether the building’s existing cabling infrastructure can support the 5G deployment, or whether a cabling upgrade is required alongside the 5G equipment installation.
A 5G small cell connected by Cat5e cabling, or powered by a PoE+ switch that cannot deliver its rated draw, will not perform at the specification the 5G vendor promised.
A 5G small cell connected by Cat5e cabling, or powered by a switch that cannot deliver its rated draw, will not perform at the specification the vendor promised.
Private 5G vs enterprise WiFi: the right questions
Private 5G is not a replacement for enterprise WiFi in most commercial office environments. The two technologies serve different use cases and should in most cases be deployed in parallel. WiFi remains the appropriate technology for staff device connectivity, guest access, and general office applications. Private 5G is the appropriate technology for deterministic low-latency connections for real-time AI applications, machine-to-machine connectivity for IoT devices that need guaranteed throughput, applications requiring outdoor-to-indoor seamless handoff, and environments where the density of connected devices exceeds what WiFi can serve reliably.
The practical implication for cabling infrastructure is that a building deploying both WiFi and private 5G needs cabling to support both, WiFi access points on Cat6A with PoE++ switching, and 5G small cells on Cat6A or fibre with their own power provision. The cabling contractor who designed and installed the WiFi infrastructure is the right starting point for the 5G infrastructure, because the physical plant is shared, and the PoE budget, VLAN design and switch architecture all need to be considered as a single system.
Both DAS and small cell approaches require structured cabling infrastructure. The question is not whether private 5G needs it, but how it must be specified.
OFCOM spectrum and the licensing requirement
Private 5G networks in the UK operate on spectrum licensed from OFCOM. Organisations deploying private 5G must either obtain their own OFCOM spectrum licence or work with a licensed operator who provides spectrum access as part of the private 5G service. The cabling contractor’s role does not extend to spectrum licensing, but the IT Director or Facilities Manager needs to ensure spectrum access is secured before the physical infrastructure is ordered.
The most common approach for commercial buildings is to work with a managed private 5G provider who licenses spectrum, supplies the core network equipment and manages the 5G infrastructure as a service. The building owner or tenant is responsible for the passive infrastructure, the structured cabling, the comms room space, and the physical mounting points for small cells or RAUs. ACCL provides the passive infrastructure element.
Warehousing and logistics: Autonomous mobile robots, real-time inventory tracking, AI-powered picking systems. WiFi cannot deliver the sub-10ms latency these applications require. Private 5G can.
Manufacturing: Machine-to-machine connectivity for AI-driven quality control, predictive maintenance and autonomous production line management. Private 5G provides the deterministic connectivity these processes demand.
Large commercial campuses: Seamless connectivity across multiple buildings, car parks and outdoor areas where WiFi coverage is impractical. Private 5G with outdoor small cells bridges the gaps.
Standards and sources
- Ofcom Shared Access licenceUK spectrum licensing for private 5G
Frequently asked questions
What structured cabling does a private 5G network require?
Private 5G networks using small cells require Cat6A cabling for data connectivity and PoE++ (802.3bt) for power delivery, as small cells draw 30 to 60W per unit. DAS-based deployments require fibre optic cabling between the head-end and remote antenna units, plus Cat6A for management connections. In both cases, the structured cabling requirements are broadly similar to those for enterprise WiFi, and the same Cat6A infrastructure that supports WiFi 7 access points can typically support 5G small cells.
Can private 5G replace WiFi in a commercial office?
Private 5G is not a replacement for enterprise WiFi in most commercial office environments. WiFi remains the appropriate technology for staff laptops, mobile devices and general office applications. Private 5G serves specific use cases requiring deterministic low latency, guaranteed throughput for machine-to-machine connectivity, or seamless outdoor-to-indoor coverage. The two technologies are complementary and are increasingly deployed in parallel in buildings with diverse connectivity requirements.
Do I need an OFCOM licence for a private 5G network?
Yes. Private 5G networks in the UK operate on spectrum licensed from OFCOM. Organisations can apply for their own spectrum licence directly from OFCOM, or work with a managed private 5G provider who holds the licence and provides spectrum access as part of their service. The spectrum licensing question must be resolved before physical infrastructure is ordered, as the spectrum band determines the small cell hardware specification.
What is a DAS and how does it differ from small cells?
A distributed antenna system (DAS) uses a central head-end unit connected by fibre to remote antenna units distributed around the building. The head-end distributes the signal to each antenna. Small cells are self-contained 5G base stations connected individually to the network by Cat6A or fibre. DAS is typically used in larger buildings where a single head-end can cover multiple floors, and is common for supporting public operator signals as well as private 5G. Small cells are more commonly used for private 5G deployments where each unit serves a localised coverage area.