By Steve Davidson
Rethinking the Data Centre Conversation
When you think of a data centre, you might imagine the sprawling new giga campuses commissioned by tech giants that dominate headlines. For many, this hyperscale model has become their perception of the sector. The reality is more nuanced, and the unprecedented pace of technological change presents complex challenges.
Equipment is becoming denser and heavier, and mechanical and electrical systems are evolving so quickly that many new facilities risk being outdated almost as soon as they come online. At the same time, a large stock of legacy data centres is reaching the end of its lease cycle. These buildings are already equipped with power, connectivity and planning consent, but many are no longer fit for purpose.
Multi-gigawatt new builds will be an integral part of our increasingly digital world, but we should also be asking ourselves, “How do we make better use of the assets we already have?”
The Role of Structural Engineering
The sector has long been driven by mechanical and electrical requirements, which makes sense because that is where the critical systems sit. For new builds, the structure is usually shaped around the services, but existing buildings are a different story. Their frames are not as flexible or easy to adapt, and the weight of new technology pushes them beyond their intended capacity. Increasing rack density adds load to the servers themselves, as well as to the ducting, cooling and power routes that support them.
This is where structural engineers come in. Before deciding what kit to install, asset owners need to understand what their structure can actually carry. For the past few years, I’ve been advocating for structural involvement at the earliest possible stage. Rather than asking an M&E partner to outline what can be fitted in, bring in the structural engineer to assess load capacity and identify the limits and opportunities within the frame. Only then can the M&E strategy be developed with confidence.
Unlocking The Structure
The challenge becomes even more pronounced in multi-let and multi-floor campuses. It’s common to see several different design partners working on isolated elements of the building, each aiming to maximise their area of fit-out. In these situations, we often step back and look at the whole picture. Enhancing one part of a building can unintentionally reduce the capacity of the floors above or below it, effectively consuming more load than the asset can support overall.
We consider the building holistically. What is the most efficient way to develop the entire asset from a loading perspective? For a relatively small fee in the data centre world, we can carry out an early forensic assessment to determine what the building can and can’t do. How can we maximise the asset for the client? That’s the crucial question. I like to call this “unlocking the structure”. Once that is understood, the M&E and architectural teams can design confidently within those structural boundaries.
Breathing New Life into Legacy Data Centres
Legacy data centres are often ideal candidates for retrofit. They already sit on sites with strong power and connectivity and have passed through the planning process. Enhancing what exists instead of building anew can also offer substantial carbon savings. Embodied carbon has already been spent on the original structure, and smart enhancement allows us to extend its life without repeating that investment. As I often say, the best building for the site is the one that’s already there.
From experience, these projects typically fall into two groups. Outside the city, some legacy facilities are simple, single-purpose buildings where the balance between refurbishment and redevelopment depends heavily on carbon and operational considerations. In dense urban locations the picture changes. Many older London data centres are multi-storey, multi-tenant and landlocked. Demolition becomes difficult, disruptive and often financially unrealistic. In these cases, a structural review is the key to unlocking future use and adding value. Quickly and cost-effectively, we can identify safe capacity, upgrade potential and an efficient plan for extending the building’s life.
Opportunities in Disused Industrial
Beyond purpose-built data centres, there is a wide range of existing buildings with potential. Older industrial buildings in particular tend to be robust, with significant inherent load capacity. If these assets sit on sites with inherited power and connectivity, they are strong candidates for repurposing. In some cases, you might retain the shell and rebuild inside or reconfigure floor plates to suit a new use.
Retrofitting on former industrial land or decommissioned power stations also has the potential to bring economic opportunity to areas left behind by deindustrialisation. Bringing them back into productive use creates skilled roles and offers a meaningful route to utilise green energy that the UK currently struggles to absorb into the grid. That same green energy is often being curtailed and paid for through public funds. Using it locally through data centre operation helps reduce baseload pressure and, in turn, household utility costs.
Rethinking Commercial Space
Central London is full of large commercial mixed-use buildings that present their own opportunities. In Canary Wharf, for example, there are office buildings that no longer serve their original purpose but could house data centre space within a portion of their footprint. This can enhance the value of the wider building, offering office tenants additional capability and opening the door to district heating, amenity spaces such as indoor allotments, and even the possibility of residential use.
Contrary to common belief, data centres do not have to sit at the lowest levels of a structure. Placing it higher in the building can command stronger rental values, and with careful load balancing the structural impacts on the foundations and basements can be mitigated.
Planning and Policy Advantages
Planning remains a major hurdle for new-build data centres. The government has classified them as mission-critical infrastructure, but applications still face long timelines and public resistance. Concerns about visual impact and power demand often dominate discussions, delaying progress before design work has even begun. Many people have a “not in my backyard” attitude to new facilities.
Retrofit avoids some of these contentious sticking points. The asset already exists, the use is established, and the proposal is usually an enhancement rather than a complete change of use. For operators, this removes significant uncertainty and accelerates delivery, allowing projects to move forward without the prolonged approvals process that new builds typically require.
A Faster, Smarter Path to Capacity
Retrofitting data centres isn’t a completely new concept, but the acceleration of digital demand is making it an increasingly viable and attractive option. Operators want the most efficient kit available as quickly as possible. That equipment is heavy, and existing facilities cannot absorb it without structural intervention. The technical challenges come back to load and what the frame can do. Servers are getting heavier and so is the supporting infrastructure; strengthening a frame may involve exoskeletons, deck upgrades or targeted reinforcement of steel or concrete. Often, the solution is simply smarter load distribution rather than major invasive work. Understanding those limits before committing to a strategy is essential.
Hyperscale data centres will undoubtedly play an important role, but they take years to deliver. Meanwhile, we have assets already built, already powered and already connected. Enhancing them helps bridge the widening supply gap. The carbon invested in constructing these buildings has already been spent, and that should not be ignored. Maximising what we have is simply better stewardship of resources. That principle alone is reason enough to look at existing assets first, but when combined with the speed, practicality and planning advantages retrofit offers, the case becomes even stronger.
A Call for Earlier Engagement
The industry wants to retrofit more, but many operators are unsure where to begin. This is where trust in a design partner is essential. My recommendation is simple: get us in early. Long before a tenant moves out or a space becomes available, we can carry out a structural review, assess the archive information, the existing kit and the frame performance, and give a clear view of what is possible.
Retrofit is a valuable and often overlooked opportunity. At Robert Bird Group, we know how to unlock an existing building, understand it in forensic detail and enhance the asset. Our structural expertise and experience across both data centres and commercial buildings make us uniquely adept in this specialist field. With the right insight at the right time, we can help operators extend the life of their assets, reduce carbon impact and bring much-needed capacity online far sooner than starting from scratch.