As energy costs rise, government Net Zero deadlines approach, and indoor environmental quality (IEQ) expectations tighten, the gap between what healthcare buildings can achieve and how they currently perform is becoming more apparent. Addressing this gap is increasingly shaping both operational priorities and longer-term strategic decision making. Darryl Gregory, VP of Sales for EMEA at Distech Controls, explains why retrofitting should be seen not as a compromise but as a key part of a strategic approach to future-proofing healthcare estates.
Across the NHS estate, there is a growing opportunity to enhance how building infrastructure supports operational performance and sustainability objectives. Thoughtfully designed retrofit programmes can help modernise building systems over time, enabling organisations to upgrade critical infrastructure in a staged and pragmatic way, while minimising disruption compared with more extensive redevelopment approaches.1 Modern retrofit programmes are a practical route to upgrading the infrastructure of a building, without the disruption of a total rebuild.
Hospitals and community healthcare facilities are unlike almost any other building type. They are energy-intensive, continuously occupied, and subject to strict regulatory requirements that govern everything from ventilation and pressure regimes to temperature and humidity. Yet, a significant proportion of the UK’s healthcare estate was built during the formation of the NHS in 1948, with over 43 per cent being built over thirty years ago and before 2000,2 designed for a different era and managed by controls that were never conceived to handle today’s data volumes, sustainability demands, or security expectations.3
The result is an estate with untapped potential. In many cases, plant and underlying infrastructure are already in place, but there is an increasing opportunity to introduce greater intelligence to support how these assets are operated and optimised.
Retrofitting as a strategic approach
Retrofitting is increasingly being recognised as part of the solution. Not as a compromise, but as a strategic approach. One that can support a faster, less disruptive, and more cost conscious pathway toward more efficient healthcare environments.
Partnering with organisations across the country on this transition has shown us that retrofit-ready technologies are now delivering measurable value, often without the disruption that would have made projects like this previously unviable.4 Today’s solutions make it possible to reuse existing cabling, equipment rooms and even legacy controllers while bringing buildings into the era of IP-native, cloud ready performance, all with far less disruption, cost, and risk than traditional refurbishment.
Commercial buildings constructed at the turn of the millennium or earlier were not designed to meet the demands of today’s digital-first operations, hybrid working models, or the increasingly stringent carbon performance standards shaping the UK property landscape.
New developments alone cannot meet the scale or urgency of today’s building performance challenges, and demolition or full redevelopment is often neither practical nor financially viable. As older commercial properties face rising vacancy rates, tighter regulatory requirements, and evolving occupier expectations, where comfort, air quality, and seamless digital services are now fundamental, retrofitting has become the most pragmatic, economically sound, and future-ready path forward.
Making existing buildings future ready
A common misconception is that a smart building must be newly built within the last 20 years or undergo a complete refurbishment. Significant performance and digital gains can be achieved by upgrading existing systems.5 Today’s technologies make it possible to retain and optimise much of the existing infrastructure, delivering advanced functionality with minimal disruption.
Most healthcare properties generate vast streams of operational data. Sensors, controllers, meters and plant communicate constantly. Yet much of that data goes unused, leaving estates teams making decisions with a fraction of the insight available to them.6 Schedules drift, setpoints go unchecked, sensors age out of calibration and systems that were once optimised become increasingly misaligned with how buildings are used.
A modern retrofit approach begins with visibility, deploying trend logs, alarms, sub-metering and analytics across priority systems, and connecting those data streams to platforms that surface exceptions, not just readings.7 This shift from reactive to proactive management is one of the most significant operational improvements a Trust can make, and it does not require replacing major plant to deliver results.8
This is why a ‘controls-first’ approach has become so compelling in healthcare settings. By targeting the supervisory layer and upgrading controllers and sensors during planned works, estates teams can capture significant energy and carbon savings without invasive intervention into clinical spaces.9 In many buildings, it is also possible to reuse elements of existing cabling infrastructure, including legacy building automation wiring, as the industry moves towards long reach Ethernet technologies and IP native control architectures. This allows buildings to move from legacy set ups with increased costs to modern, interoperable networks without opening ceilings, replacing cabling or estates being unable to use the premises during works. The result is significantly lower project costs.
The adoption of open protocols and interoperable platforms helps mitigate reliance on proprietary vendor ecosystems that may restrict upgrade pathways and contribute to higher long-term costs. This shift provides healthcare estates access to a broader ecosystem of solutions, enabling greater choice, competitive procurement, and the integration of best-in-class technologies. It also allows them to leverage advanced analytics and energy optimisation tools while positioning their assets to adopt emerging innovations, such as cloud services and AI-driven automation.
The practical benefit in live clinical environments is considerable. Reduced rewiring means less disruption.10 Staged rollouts can be aligned with ward refurbishments, departmental moves, and lifecycle replacement schedules, fitting around clinical priorities rather than competing with them.
Strengthening cybersecurity
As commercial buildings become more connected, it is increasingly important that the controllers operating them are secure and can be kept up to date with the latest firmware and software. Healthcare operates within a highly regulated and availability critical environment, shaped by factors such as extended device lifecycles, defined maintenance and update windows, and the need to sustain continuous clinical operations. These considerations influence how digital technologies, including those supporting the built environment, are deployed and managed over time. The NHS’s Digital Technology Assessment Criteria (DTAC)11 reflect an industry-wide expectation that security assurance is now a baseline requirement, not an optional feature, and that expectation is extending, by necessity, from clinical devices to building infrastructure.12
What a secure retrofit looks like in practice
- Replacing or segmenting legacy protocols where they cannot support modern security controls.
- Reducing unmanaged remote access and moving toward controlled, authenticated, monitored connectivity.
- Improving asset visibility and documentation of OT architecture across estates and IT teams.
- Applying security-by-design principles to all new controllers, gateways, and supervisory platforms.
- Aligning upgrade programmes with NHS cybersecurity expectations and evolving OT maturity frameworks.
A fast route to sustainability compliance
Retrofitting is an effective way to meet sustainability and carbon reduction goals,13 allowing building owners to replace outdated control systems with high efficiency, interoperable alternatives that help to reduce energy consumption, lower emissions, and support compliance with evolving UK regulations. Crucially, retrofit-ready technologies enable faster, low disruption installation through modular components and cable reuse approaches, minimising downtime and inconvenience for buildings that remain fully occupied or operate on tight schedules.14
The NHS’s commitment to Net Zero — 2040 for direct emissions, 2045 for those it can influence — is not aspirational language. It is embedded in healthcare governance and estate planning, with Trusts expected to move beyond high-level pledges and deliver measurable, auditable progress.15 For most NHS organisations, the existing estate is where the largest gains are available, and where the pressure is most immediate.
Deep decarbonisation, plant replacement, heat pump transitions, and fabric improvements require significant capital and lead time. Controls and monitoring upgrades do not. Case studies published in the CIBSE Journal demonstrate that BMS optimisation, combined with improved data visibility, can deliver energy reductions of up to 28 per cent without major capital works.16 For healthcare buildings, where outpatient clinics, meeting rooms, admin areas, and teaching spaces are frequently unoccupied or partially used, smarter scheduling and demand-responsive control can be particularly powerful: matching ventilation, heating, and cooling usage to real occupancy patterns rather than fixed assumptions.
Critically, these interventions also generate the data infrastructure needed to make the case for larger capital investment. When Trusts can demonstrate precisely where energy is being lost, how systems are performing against design intent, and what the carbon impact of specific interventions would be, the business case for deeper retrofit becomes far easier to justify.
Working together for retrofit success
Energy and carbon are not the only story. In healthcare settings, the built environment has a direct bearing on clinical outcomes,17 staff wellbeing, and infection control. Ventilation is not merely a comfort consideration, it is clinical infrastructure, subject to detailed national guidance under HTM 03-01, which sets out design, operational, and performance verification requirements for specialised ventilation in healthcare premises.
The challenge is that ventilation performance degrades over time. Sensors drift, and systems that were commissioned correctly operate against occupancy patterns that have shifted. Faults go undetected until they become significant. When retrofit programmes improve monitoring, introduce fault detection and diagnostics, and increase maintenance visibility, they help estates teams maintain performance more consistently, respond pro-actively when conditions drift, and provide the assurance reporting that clinical governance requires.
A practical retrofit roadmap for healthcare estates
Successful programmes treat building performance as a continuous journey rather than a single project. The following staged approach is designed for live clinical environments and aligned to improving outcomes.
1. Baseline, governance and quick wins
Build an asset inventory and identify priority areas: critical ventilation, high-energy plant, high-complaint zones. Deploy metering and trend data capture. Optimise schedules, setpoints, and control strategies, especially for out-of-hours operation. Validate ventilation and IEQ performance where clinical risk is highest.
2. Modernise controls and connectivity
Replace end-of-life controllers and gateways with IP-capable, open-protocol alternatives. Improve network segmentation and secure remote access. Standardise naming conventions, documentation, and handover processes to reduce long-term complexity and support IT alignment.
3. Scale analytics, fault detection and continuous improvement
Expand monitoring and exception-based maintenance workflows. Use performance verification and benchmarking to identify drift and sustain gains. Establish a rolling optimisation cycle aligned to seasonal recommissioning and quarterly reviews.
4. Deep decarbonisation aligned to the Net Zero pathway
Use controls data to de-risk and prioritise larger plant investment decisions. Align retrofit packages with NHS Net Zero trajectories and reporting expectations. Target measures that reduce operational energy intensity while maintaining clinical performance.
What gets in the way and how to overcome it
Healthcare retrofit programmes often need to be delivered within a set of well understood constraints: live environment constraints and infection prevention protocols;18 the complexity of multi-generational control systems; competing capital priorities; skills gaps in specifying and maintaining modern digital systems; and the challenge of aligning estates upgrades with IT security governance.19
The good news is that a modern retrofit strategy addresses these concerns directly. Phased delivery models allow investment to be staged. Robust data platforms make business cases for further spend straightforward to construct and defend. And collaborative delivery approaches that bring together estates, IT, clinical leadership, and specialist partners reduce the risk of siloed decision-making that can undermine outcomes.
Open-protocol environments are particularly important here. They can reduce dependency on any single vendor’s roadmap, allow systems to be upgraded in stages, and make it easier to integrate technologies over time. In complex healthcare environments, where clinical needs evolve continuously and systems must adapt to match, that flexibility is not a luxury. It is a requirement.
Retrofit is not a compromise
The framing of retrofitting as an alternative to new build is the reality of NHS estate management. For most Trusts, retrofitting is not just a more affordable option, it is a realistic one. The buildings the NHS relies on today will still be here in 2040, and an effective way to ensure they are performing as they should is to invest in the intelligence that runs them.
With Net Zero targets setting a clear timeline, HTM 03-01 establishing clinical performance expectations, and cyber resilience becoming a baseline requirement,20,21 the case for a co-ordinated, outcomes-led retrofit programme has never been stronger.
Our approach centres on providing healthcare estates the freedom to choose the expertise and solutions that best suit each project. By championing open, interoperable systems, it can help make collaboration with a wide range of specialists easier, reduce project risk, and ensure a seamless transition from legacy infrastructure to future ready platforms.
This partnership centric model delivers the agility, continuity, and long-term adaptability essential for upgrading buildings that must remain operational throughout the process.
Retrofitting is not a compromise but a strategic investment in the future of commercial property. While legacy systems create unnecessary complexity, cost, and vulnerability, modern cloud enabled, open standard controls provide unified, adaptable networks that can evolve with tomorrow’s technology. As the UK moves rapidly toward a low carbon, digitally driven built environment, retrofitting will determine which buildings remain competitive and relevant.
Darryl Gregory
Darryl Gregory is vice president of sales, EMEA at Distech Controls, part of Acuity Brands’ Intelligent Spaces Group, where he leads sales strategy and execution across Europe, the Middle East, and Africa. With nearly 25 years in building automation and controls and BMS sector, he is known for delivering sustained commercial growth. Prior to joining Distech Controls, Darryl spent 18+ years at Honeywell in senior UK/I and Northern Europe sales leadership roles.
References
1 https://www.gov.uk/government/publications/demolition-and-redevelopment-or-retrofit-research-report
2 https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/607725/Naylor_review.pdf
3 https://www.england.nhs.uk/publication/specialised-ventilation-for-healthcare-buildings/
4 https://insights.acuitybrands.com/distech-controls-project-references-blog/st-columbas-school-kilmacolm-uk
5 https://www.cibsejournal.com/technical/back-in-control-how-bms-optimisation-saved-171000-in-nine-months/
6 https://www.fmj.co.uk/expert-insight-nhs-estates-teams-struggle-with-maintenance-backlog-as-fragmented-asset-data-risks-patient-safety/
7 https://betterbuildingssolutioncenter.energy.gov/sites/default/files/building_fault_detection_and_diagnostic-paper.pdf
8 https://healthcare-property.com/features/getting-smart-with-hospital-maintenance/
9 https://www.buildingbetterhealthcare.com/index.php/healthcare-estates-shift-from-reactive-maintenance-to-data
10 https://digital.nhs.uk/services/networks-and-connectivity-centre-of-excellence/connectivity-hub/advice-and-guidance/smart-theatres/smart-theatres
11 https://transform.england.nhs.uk/key-tools-and-info/digital-technology-assessment-criteria-dtac/
12 https://digital.nhs.uk/cyber-and-data-security/guidance-and-assurance/guidance-on-protecting-connected-medical-devices
13 https://www.cibsejournal.com/cpd/modules/2026-01-rsaeb/
14 https://ez.analog.com/ez-blogs/b/engineerzone-spotlight/posts/how-old-wires-are-bring-new-efficiencies-to-building-retrofits
15 https://www.england.nhs.uk/greenernhs/a-net-zero-nhs/
16 Back in control: making savings with BMS optimisation – CIBSE Journal
17 https://www.tandfonline.com/doi/pdf/10.1080/09613218.2017.1411130
18 https://www.england.nhs.uk/publication/infection-control-in-the-built-environment-hbn-00-09/
19 https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/607725/Naylor_review.pdf
20 https://www.england.nhs.uk/greenernhs/a-net-zero-nhs/
21 https://www.england.nhs.uk/publication/specialised-ventilation-for-healthcare-buildings/