Case study 2 City Walk, Leeds

Indoor environmental monitoring using smart sensor technology from Airthings, providing healthier working environments for building occupants.

2 City Walk is a multi-tenanted landmark office building occupying a prominent position in Leeds South Bank. Built in 2003 and comprising a total floorspace of 64,115 sq ft, arranged over six floors plus two floors of sub ground car parking, the property has an Energy Performance Certificate (EPC) rating of Band C and includes a 4 pipe fan coil, heating, ventilation and air conditioning (HVAC) system.

In February 2021, building managers for 2 City Walk, requested a trial of the Airthings for Business smart indoor air quality monitors, to assess indoor air quality and virus transmission risk in the building. During a Covid-19 lockdown, when the building was empty, one of our engineers deployed 19 Airthings for Business Wave Plus monitors and three hubs across the building’s six floors. This enabled our team to analyse and adjust indoor environmental conditions to provide a safe working environment when building occupants returned.

Low temperature and humidity identified during lockdown

During lockdown whilst the building was empty, initial data from the sensors showed indoor air quality to be good, but that temperature and humidity levels were low, creating a high virus transmission risk score. This was unsurprising as the HVAC system had been put into caretaker mode during lockdown to save energy and as the building was unoccupied there was no risk to employees at that time.

On the lifting of the lockdown and before employees returned to the workplace, our team reinstated the HVAC system, and adjusted the settings to ensure optimal environmental conditions were obtained throughout the building, to ensure a safe and comfortable environment.

The graphic below shows the values for humidity, temperature and virus risk whilst the HVAC system was in caretaker mode and after the lockdown when occupants had returned to the workplace.

Evotech Air Quality continues to remotely monitor the indoor environment at 2 City Walk ensuring tenants and their employees breathe clean, healthy air whilst at work. Our team keeps humidity between 40 and 60 percent and ventilation rates are set at 6 air changes per hour with filtered outdoor air maximised over recirculated air, to help prevent the spread of viruses.

Evotech's main objective is to help our clients provide safe, healthy indoor spaces, using IOT technology advancements. In addition to improving air quality, IAQ sensors can be integrated with a building management system to save energy and reduce carbon emissions. To do this, we provide enhanced environmental sensors above and beyond what a traditional building management system provides. By utilising real time data from Airthings IAQ sensors, we can optimise how buildings perform and achieve greater levels of energy efficiency. What’s more, the IAQ sensors can alert our team to issues with the HVAC system, so they can resolve them quickly, even before clients report it.