A multi-tenant office building was experiencing recurring complaints about “stuffy” meeting rooms and inconsistent comfort during busy periods.

Ventilation was controlled using fixed, time-based schedules. This meant air was often supplied to empty spaces, while heavily occupied rooms did not always receive enough fresh air. The Facilities Management (FM) team wanted a more responsive approach that would improve indoor air quality (IAQ), support modern wellness standards and enable data-led operation.

The challenge

The building faced several issues:

  • Poor air quality in busy meeting rooms during peak use.

  • Energy waste from ventilating underused areas.

  • A reactive approach, relying on complaints rather than live data.

  • A desire to align with performance-based standards such as WELL and RESET.

The objective was clear: move from time-based ventilation to demand-led control, delivering fresh air where and when it was genuinely needed.

The solution

Sontay RF-LW-TIAQ Indoor Air Quality sensors were installed in meeting rooms and shared spaces. These wireless devices continuously monitor:

  • CO₂

  • Temperature

  • Humidity

  • VOCs

  • Particulates

The sensors communicate via LoRaWAN to a Sontay RF-LW-HUB-EU868-100 gateway. The gateway integrates directly into the existing BMS over BACnet IP, providing a straightforward and fast integration path.

How it works

The IAQ data feeds directly into the building’s HVAC control strategy:

  • When CO₂ levels rise in occupied spaces, the BMS automatically increases fresh air supply to that zone.

  • When spaces are lightly occupied or empty (validated using occupancy and lighting data), ventilation rates are reduced.

Ventilation is now demand-led rather than time-based. Comfort is maintained, while fan and heating/cooling energy is reduced.

Because RF-LW-TIAQ continuously measures multiple IAQ parameters, the system also supports performance-based approaches aligned with standards such as WELL and RESET, when designed and documented appropriately within a certification framework.

Greater visibility for tenants and FM

Live dashboards built from RF-LW-TIAQ data provide clear visibility throughout the day.

For tenants:

  • Real-time IAQ visibility builds confidence in environmental quality.

  • Meeting rooms feel fresher and more consistently comfortable.

For the FM team:

  • Temperature and humidity trends confirm comfort bands are maintained.

  • VOC and particulate data highlights activities affecting air quality.

In one example, elevated VOC and PM10 levels revealed the impact of cleaning activities. This allowed the FM team to adjust scheduling and ventilation timing more effectively.

The results

Although the primary aim was to ensure ventilation is delivered “when required and where required,” the solution delivered wider benefits:

  • Significant reduction in complaints about stuffy rooms.

  • Better-targeted ventilation energy use.

  • Evidence-based maintenance, such as filter checks triggered by IAQ data instead of fixed intervals.

  • Continuous multi-parameter monitoring supporting modern IAQ and wellness expectations.

  • Increased tenant trust in the building’s environmental performance.

Customer feedback

Tenant feedback:

“Having visibility of air quality in our meeting rooms is reassuring. We know the system is increasing ventilation when CO₂ levels rise, and the rooms feel fresher and more comfortable throughout the day.”

FM team feedback:

“The RF-LW-TIAQ sensors have changed how we operate. Integration of the LoRaWAN hub into our BMS over BACnet IP was quick and straightforward, and Sontay’s service throughout the project has been first class. We no longer wait for complaints – we can see temperature, humidity, VOC and particulate trends and intervene early. It’s reassuring to know the data from the RF-LW-HUB-EU868-100 and RF-LW-TIAQ devices is actively used, not just installed and forgotten.”

Summary

By deploying Sontay RF-LW-TIAQ Indoor Air Quality sensors and the RF-LW-HUB-EU868-100 LoRaWAN gateway, integrated into the BMS via BACnet IP, the building has moved from reactive, complaint-driven ventilation to a proactive, demand-led strategy.

Fresh air is now delivered precisely where and when it is needed. Comfort has improved, energy use is better targeted, and the building has a strong data foundation to support maintenance decisions, tenant confidence and alignment with modern IAQ and wellness standards.