What is a smart building and how did we get here?
What we now describe as a smart building is often framed through technology, yet its significance lies in a deeper shift in how buildings are expected to perform. Imogen Butterworth, New Project Engineer at Sontay, reflects on how commercial and civic buildings operated 35 years ago, largely silent, schedule driven and disconnected, and contrasts this with today’s demand for buildings that are responsive, efficient and centred on human experience.
A smart building is often introduced as a collection of technologies, but it is better understood as a change in intent. It is a building that pays attention. It senses what is happening inside it, translates that into usable information, and then acts quietly and continuously to create a better experience for the people within, while consuming less energy and producing fewer unintended consequences. In that sense, smart is not a badge; it is a behaviour.
To understand why this matters, it helps to look back around 35 years. In the late 1980s and early 1990s, most commercial buildings were designed to be solid, reliable and predictable. Heating and ventilation were engineered to meet a fixed set point and a timetable. Lighting was typically manual or controlled by simple time clocks. Control strategies were often set at commissioning and rarely revisited. Systems operated independently, data was scarce and buildings had little awareness of how they were actually being used. Comfort was assumed rather than measured, and inefficiency often went unnoticed.
Changing expectations
What has changed since then is not simply the sophistication of equipment, but the expectations placed upon buildings. Today, we ask them to do far more than provide shelter and basic comfort. We expect buildings to support wellbeing, protect productivity, respond to fluctuating occupancy and contribute meaningfully to sustainability targets. Buildings are no longer passive assets.
They are expected to respond to the reality of daily use. The recent decision to grant the Southbank Centre Grade 2 listed status reflects this broader cultural shift. Long debated and often misunderstood, the complex is now recognised for its architectural and civic value. Its listing is a reminder that buildings are judged not only on how they look, but on how they serve people over time. As we preserve buildings of significance, we are also challenged to ensure they remain comfortable, efficient and relevant in a world very different from the one they were built for.
This is where the modern understanding of smart buildings becomes tangible. A smart building is aware. It continuously measures temperature, humidity, air quality, light levels and occupancy. It uses this information to coordinate systems that once worked in isolation. Heating responds to real demand rather than fixed schedules. Ventilation adapts to indoor air quality rather than worst case assumptions. The result is not more complexity, but calmer, more deliberate operation.
Sensing
At the heart of this responsiveness is sensing. Sensors provide the insight that allows buildings to move from assumption to understanding. Over recent decades, Sontay has played a quiet but essential role in this shift, helping building services systems better understand what is actually happening within occupied spaces.
Across a wide range of environments, this approach has helped make buildings more comfortable in very practical ways. In commercial offices, improved environmental sensing has supported more stable temperatures and better air quality, reducing the peaks and troughs that occupants often associate with discomfort. In education settings, sensing has helped maintain consistent conditions throughout the day, even as occupancy and use patterns change between lessons, lectures and events.
In healthcare and care environments, where comfort and consistency are particularly important, accurate sensing has helped buildings respond more sensitively to real conditions, supporting both occupant wellbeing and operational confidence. Residential and multi-occupancy buildings have similarly benefited from improved control, with environments that feel calmer and more predictable, rather than overcontrolled or reactive.
Gentle modernisation
Increasingly, this has also meant improving comfort in buildings that were never designed to be smart. Wireless sensing technologies have allowed upgrades to take place with minimal disruption, making it possible to enhance performance in occupied, operational and heritage buildings alike. Where rewiring is impractical or intrusive, wireless devices provide a way to modernise gently, improving how a building behaves without altering its character.
The common thread across these sectors is not technology for its own sake, but attention. By giving building systems better awareness of real conditions, sensing enables quieter, more balanced operation. The result is spaces that feel more comfortable simply because the building is responding appropriately, rather than rigidly following assumptions set years before.
Ultimately, a smart building is defined less by what is installed and more by how it behaves. It responds to reality rather than assumption. It treats energy as a valuable resource and comfort as a daily requirement. And it demonstrates its intelligence not through visible complexity, but through the quiet consistency of spaces that simply work, supporting people, conserving resources and remaining relevant long after their original design brief has faded.
