Comfort, efficiency and health
Newly appointed BCIA President Jen Vickers highlights the untapped potential of building energy management systems.
Buildings are expected to deliver lower carbon, lower cost and healthier internal environments, without compromising comfort or performance. The Building Controls Industry Association’s (BCIA) technical white paper, “Comfort, Efficiency and Health: The Untapped Potential of Building Energy Management Systems”, highlights an opportunity already within the UK’s non-domestic building stock: smarter use of building energy management systems (BEMS).
Many buildings already have the capability to operate more sustainably, but without regular reviews, performance checks and ongoing optimisation, they fail to perform as effectively as they could. Insufficient oversight of existing BEMS means systems are often underutilised, preventing buildings from achieving the full sustainability benefits that could be achieved through properly managed systems or small upgrades.
The BCIA produced the white paper to provide evidence of what advanced controls can deliver. Launched at the House of Lords, it contributes to the national discussion on accelerating progress on Net Zero and improving building performance. The key finding is clear: advanced BEMS upgrades are one of the most cost effective and scalable retrofit interventions available for non-domestic buildings, delivering carbon reduction, operational efficiency, occupant comfort and indoor air quality (IAQ) benefits.
Building controls are now business-critical
Non-domestic buildings are being asked to do more under tougher conditions: rising energy prices, constrained budgets, tightening regulations and shifting occupancy patterns. Building controls must move from being treated as a technical detail to being recognised as a performance enabler. The BCIA sees first-hand how much avoidable waste and discomfort is driven by insufficient integration, commissioning and optimisation.
Common issues remain widespread: systems running too long, ventilation rates fixed regardless of occupancy, heating and cooling competing, setpoints drifting, seasonal strategies left unchanged. BEMS provides the intelligence layer required to improve visibility, enable demand-led operation and ongoing optimisation.
What ‘advanced BEMS’ means in practice
There is a clear distinction between basic controls and high-performing BEMS strategies. The BCIA’s white paper focuses on outcomes associated with Class A BEMS, aligned with EN ISO52120, where systems support integrated, whole-building optimisation rather than isolated time scheduling. Class A controls deliver demand-based HVAC and lighting operation, improved zoning, setpoint optimisation, performance monitoring and fault detection. Enhanced by analytics and remote optimisation, these enable building performance to be managed continuously.
This level of control matters even more as the UK transitions towards electrified heating and more complex low carbon services. Without robust controls, even high-efficiency systems will underperform.
The measurable results: energy savings and payback
For those responsible for retrofit decision-making, the question is simple: what results can be achieved – and how quickly? Modelling for a typical 1,000m² office building, upgraded from Class C to Class A BEMS, shows potential energy savings of 710MWh over 10 years (around 71MWh annually) and emissions reductions of 104-105 tonnes of CO2e over the same 10-year period. Payback is achieved in just under four years, with £23,485 in discounted savings over a 10-year system lifetime. Upgrading to Class A BEMS in the office archetype is shown as the most cost effective intervention assessed, delivering carbon savings at £224 per tonne of CO2e abated, with 104 tonnes saved over a decade.
Comfort and resilience
Comfort is one of the clearest indicators of whether building services are operating effectively. Unstable temperatures, uncontrolled overheating and inconsistent response to occupancy are often symptoms of wider operational inefficiency. As high-temperature events become more frequent, comfort control is also a resilience issue. Buildings need strategies that respond dynamically to changing external conditions and internal demand, without excessive energy use. Advanced BEMS enables this through tighter control, improved coordination and continuous adjustment.
IAQ and health outcomes
Ventilation and IAQ are now central to how buildings are judged. Air quality affects wellbeing, cognitive performance and the risk of airborne illness transmission. Organisations increasingly expect indoor environmental conditions to be managed and evidenced, not assumed.
BEMS supports this through demand-led ventilation strategies, monitoring and improved operational control – delivering healthier indoor environments while managing energy consumption responsibly. Modelling suggests improved IAQ supported by advanced BEMS could prevent two-million sick days every year and enable 552,000 more pupils to succeed in national exams.
The productivity dividend
The impact of internal conditions is increasingly understood in economic terms. Modelling indicates that improved comfort in offices could yield £5.29 billion in annual Gross Value Added (GVA) in 2025, rising to a projected £12.75 billion by 2050. Total productivity improvement linked to improved comfort and ventilation is estimated at 2.25%–2.39%, with variation by sector and working patterns.
A national opportunity
The scale of the opportunity is substantial. Upgrading office, hospital and school buildings to higher-class controls is projected to deliver 15 million tonnes of CO2e savings between 2026 and 2035, equating to an annual reduction of 7.4% in emissions across all UK commercial and public sector buildings.
The BCIA believes these results demonstrate a clear opportunity for policymakers, public estates and the wider supply chain to prioritise building controls as core retrofit infrastructure. Yet advanced controls remain underprioritised, often treated as optional, value-engineered out, or installed without the commissioning and optimisation required to unlock full performance. This creates a fundamental risk. The UK can invest in efficient, low carbon building services equipment, but without the control layer that enables it to perform optimally, outcomes will fall short.
BEMS at the centre of retrofit strategy
BEMS should be seen as essential infrastructure for delivering Net Zero-ready buildings that perform in practice. The BCIA is calling for advanced controls to be prioritised across non-domestic estates, particularly in offices, schools and hospitals. With the right specification, commissioning and ongoing optimisation, BEMS turns building services from fixed operation into measurable performance – and should be treated as a first step in any serious retrofit strategy.
This means building controls must be:
• Specified early, not added late
• Delivered to the right performance class, not minimum compliance
• Commissioned properly, with validated strategies and outcomes
• Maintained and optimised continuously, not left to drift
If the UK is serious about improving energy efficiency, delivering healthier indoor environments and closing the building performance gap, then controls must move up the agenda. Advanced BEMS is practical, proven and immediately deployable – and it is time it is recognised as fundamental to achieving these ambitions.
