The Performance Gap: bridging the divide between building design and energy consumption

The Performance Gap is a well-known phenomenon that describes the divergence between the energy consumption predicted in the design stage of a building and the energy use in actual operation. Assumptions about how a building will be used and occupied may not accurately reflect real-life scenarios. But most importantly, many buildings lack comprehensive monitoring systems that track energy usage on a day-to-day basis. Without this data, it becomes extremely difficult to identify deviations from the expected performance. Leading to higher-than-predicted operational costs, higher carbon emissions and a lack of comfort. 

Without continuous monitoring and analysis, the Performance Gap will continue to widen. 

How monitoring wellness can boost comfort, productivity and savings

The benefits of monitoring wellness in buildings go beyond just meeting sustainability goals. A well-monitored building can increase occupant comfort and productivity while reducing operational costs through optimised energy usage. Yet, unlike the energy we consume to provide a nice habitable environment or the carbon we emit in consuming this energy, it is not so simple to provide a single scoring metric representing a building’s Wellness performance.

The key to building wellness

Effectively monitoring wellness performance in buildings requires a comprehensive approach that considers multiple indicators across different disciplines. It includes aspects like indoor air quality, thermal comfort, lighting levels, acoustics, ergonomic design, access to nature, and overall psychological well-being within a built environment.

  • Particulate matter

Central when it comes to monitoring is particulate matter. Particulate matter has become more commonly associated with pollution and, therefore, physical well-being within buildings. Monitoring the particulate matter allows us to get a better understanding of how clean the air we breathe is.  

  • CO2-levels

CO2 levels indicate both the occupation levels and ventilation rates in our buildings. High CO2 levels are a proxy for low O2 levels and, therefore, inadequate ventilation levels. As you might’ve experienced yourself, human beings simply don’t function well with low oxygen levels: decision-making becomes impaired, we feel physically ill and become fatigued. If CO2 levels in certain building areas consistently exceed recommended limits, it may indicate a problem with ventilation systems or occupancy patterns that must be addressed. By identifying and rectifying such issues, occupant comfort and productivity can be improved while reducing the risk of health-related problems such as headaches or respiratory issues.

  • Temperature and thermal comfort

Some like it hot, some like it cold. Temperature set points are always a source of conflict in shared spaces, and for that reason, it is generally accepted that we can satisfy, at best, 80% of occupants most of the time. To create a policy around the temperature set points (and the associated dead bands), we need to have access to the information required. Measuring the temperature levels on each floor and within each space allows us to ensure comfortable spaces and take sustainable, energy-saving measures where needed.

  • Relative Humidity

When it comes to creating a comfortable and productive work environment, humidity control and air conditioning play a crucial role. Maintaining optimal humidity levels and providing adequate cooling is essential for the health, well-being and efficiency of occupants. High humidity can lead to feelings of discomfort, stickiness and overall decreased productivity. High humidity levels can encourage the growth of mould and bacteria, which can lead to respiratory issues such as allergies or asthma. In ASHRAE Standard 62.1-2022 they recommend that to avoid mould growth, moisture levels should be limited to a dew point of 15ºC, which at 20ºC is a humidity of 73%.

  • Light levels

An often overlooked aspect of wellness in our buildings is the lighting levels in the spaces. The right amount of light can have a significant impact on occupant well-being and overall satisfaction. Monitoring lighting levels can help identify areas where insufficient illumination might lead to eye strain or reduced productivity. By adjusting lighting fixtures or introducing daylighting strategies, both the well-being and energy efficiency of the building can be enhanced.

Harnessing data to close the Performance Gap

By collecting data on these indicators over time and analysing them against established benchmarks or standards, such as LEED or WELL Building Standard®, we can gain valuable insights into how our buildings perform in terms of wellness. This fact-driven approach allows for targeted interventions and improvements to be made where necessary.

When we translate all this data into clear information, we will know exactly how our buildings perform. Using these advanced technologies, we can bridge the divide between predicted and actual energy consumption – closing the Performance Gap and contributing to a more sustainable future.