In just one day, UK office buildings needlessly waste a year’s CO₂ from 3470 homes

As UK temperatures surge past 30° C once again, a shocking new analysis by building analytics platform Demand Logic reveals that operational inefficiencies in UK office buildings are causing massive, and preventable, carbon emissions.

According to live data, UK office heating systems continue to operate during heatwaves, contributing to over 29.1 gigawatt hours of natural gas consumption in a single day. That is equivalent to the annual consumption of 3470 UK homes, resulting in 5843 tonnes CO₂-e of emissions in just 24 hours.

‘The UK is literally heating buildings during a heatwave,’ said Mike Darby, CEO of Demand Logic. ‘Our data shows this is not an edge case. It is widespread, and it is costing the planet dearly. This shows the importance of adapting building operations to match today’s climate conditions, not just relying on legacy settings. It is totally fixable.’

The issue lies in how office heating and cooling systems are configured and maintained. Occupants requesting cooler conditions during hot weather often trigger air conditioning. If heating systems haven’t been shut off or recalibrated, the building can end up both heating and cooling itself simultaneously. Demand Logic’s platform, which captures second by second data from across millions of square metres of office space, confirms that this paradox is still the norm in many buildings.

‘We are seeing UK office buildings waste the annual energy of an average home every 25 seconds, and that is just from heating,’ added Mike. ‘When you add the extra energy needed to cool these overheated spaces, the numbers get even worse.’

Even among environmentally progressive offices, the company recorded 384 Wh of heating energy waste per square metre of office space on a more than 30° C day, costing an estimated £2.6 million in gas nationally. With the wider UK building stock likely performing worse than the more environmentally and operationally conscious sample group, the true figures are likely to be considerably higher.

The root causes range from faulty valves to poorly calibrated set points and misaligned sensor readings. Many buildings also operate on outdated control systems not designed for modern climate conditions.

But the solutions are already within reach. Demand Logic’s analysis points to simple, low cost steps:

• Repair or replace broken valves and sensors.

• Adjust overlapping heating and cooling thresholds.

• Reconfigure control systems based on real use patterns.

• Conduct regular performance reviews using real time data.

‘Too many building owners think energy savings require massive capital investment,’ said Mike. ‘In reality, it can start with better using what you already have. Buildings need to be retuned like a car or an orchestra. Right now, too many are playing out of sync.’

The analysis highlights a broader challenge. Most UK commercial buildings were designed for milder weather. A 2019 study predicted that by 2050, London’s climate will resemble today’s Barcelona. Yet 72% of the buildings that will exist in 2050 have already been built, and retrofitting them to cope with future climate extremes will be vital.

‘We are not just wasting money or energy, we are undermining our ability to adapt to climate change,’ concluded Mike. ‘If we can’t get this right now, while it is still optional, the cost of waiting will be far greater.’