How does smart building automation help to keep buildings pleasantly cool even on hot days?Reto Decurtins: An automated system works proactively rather than reactively. It knows the position of the sun, the room temperatures, the occupancy and the weather forecast, and intervenes before the building heats up. This allows shading, ventilation and cooling to be controlled optimally: the shading prevents heat from entering the building in the first place, the cool night air is used in a targeted way, and cooling is only used where it is actually needed.The result is a stable indoor temperature with significantly lower energy consumption.

Why do shading, ventilation and cooling have to function as an overall system?The crucial difference lies not in the individual components, but in how they interact. Modern buildings almost always have sun protection, but its potential is often not fully utilised – for example, due to manual overrides or inadequate control. In the optimum case, shading, ventilation and cooling work together with a shared logic. The shading responds automatically to the position of the sun and heat load, the night is used for free cooling, and the cooling only takes care of fine adjustment.The basic idea also applies without automation: anyone who uses blinds and windows at the right time can already significantly reduce the heating-up of a building. The greatest levers often lie in preventing heat from entering the building in the first place and making targeted use of the cooler night-time and morning hours.Comfort increases and, in practice, energy consumption is often 20 to 40 per cent lower.

Where is energy often wasted unnecessarily during a heatwave?Typical mistakes include raised blinds while cooling is running, open windows in air-conditioned rooms, or setpoint temperatures that are set too low. In summer, 24–26 °C (or even higher on very hot days) is perfectly comfortable. Empty rooms or entire sections of buildings are also often cooled unnecessarily, while free night-time cooling remains unused.Building automation prevents such situations through intelligent control: it takes into account window contacts, occupancy, time programmes and temperature settings, ensuring that cooling is only provided where it is actually needed.Can buildings already respond to upcoming hot days thanks to weather data?Yes. Modern building automation can use weather forecasts and recognise as early as the previous evening that a hot day is ahead.The control system then uses the night for targeted cooling and charges the building’s thermal storage mass “cold” for the next day. This so-called predictive control is already standard in modern buildings today.The limiting factor is usually not the technology, but whether someone thought during the planning stage to activate this intelligence as well.Learn more

What will heat-resilient buildings of the future look like?They combine intelligent control with good building physics: automated sun shading, green roofs and façades, thermal mass, and efficient cooling and ventilation systems.In future, buildings will take even greater account of weather data, occupancy and available energy, and actively prepare for heatwaves.The vision is of a building that largely organises the heatwave away itself, rather than combating it with brute-force cooling capacity.

Expert networkAs an installation and technology provider, BKW Building Solutions and its expert network are able to supply customers with solutions and components that are coordinated, customised, compatible with one another and can be continuously expanded. With this approach, future trends and changing needs are no obstacle to a successful transition to a more environmentally friendly future.

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