What Gensler’s Green Wall Study Means for Healthier Workplaces
Most of the decisions that shape organisations are made in meeting rooms. These spaces are where strategies are agreed, risks are weighed and long-term priorities are set. Yet the environments in which these decisions take place are rarely examined for how well they support human health, cognitive performance and overall wellbeing.
Meeting rooms and offices are typically enclosed environments, heavily reliant on mechanical ventilation to maintain acceptable indoor air quality. When air quality declines, even subtly, it can affect concentration, alertness and decision-making.
Addressing the growing challenges of pollution and poor air quality is critical for human health. These challenges are not confined to outdoor environments; they extend indoors as well.
At present, indoor air quality is typically controlled through mechanical ventilation systems designed to regulate concentrations of carbon dioxide (CO2), particulate matter (PM2.5) and total volatile organic compounds (TVOCs). While effective, this approach carries a notable drawback: reliance on mechanical systems increases building energy consumption, undermining sustainability, resilience and operational efficiency, while also raising running costs.
Over time, these systems can inadvertently contribute to the very pollution they aim to mitigate due to increased energy demand and fuel use. Managing indoor air quality through the integration of living walls offers a potential alternative, with meaningful benefits for occupant health and experience, as well as for overall building performance.
A six‑month study by Gensler provides robust evidence that green walls can deliver tangible environmental and human benefits inside real offices, not just in lab conditions.
What Gensler Tested and Why It Matters
Gensler’s Shanghai office hosted a controlled experiment in a real-life working environment: two identical conference rooms, one fitted with a living wall, specifically using plant species known to target indoor air pollutants and improve indoor air quality levels, and one kept as a standard space. The plans, furniture fit-out and ventilation of the two rooms were identical.
Over a six-month period, the team monitored levels of CO2, PM2.5, TVOC, relative humidity (RH) and temperature in the two rooms. They also surveyed 60 staff members about their experience and preferences.
the results
The living wall showed significant, positive improvements to indoor air quality over the course of our study:
- CO2 reduced by 24% in the green room compared to the control, while PM2.5 (the very fine air pollution that can harm health when inhaled) fell by 21% – both meaningful improvements for cognitive function and respiratory health.
- The green room recovered faster to baseline indoor air quality after disturbances – important for resilience on days with poor outdoor air quality.
- The presence of the living wall kept the green room comparatively warmer than the control room.
- 79% of users reported health benefits; 65% preferred the room with the living wall; and 70% felt happier in the green space.
These findings align with broader biophilic design evidence and provide a practical blueprint for implementation in typical office contexts.
Why should facilities teams act on this? Because indoor air quality and employee experience drive measurable outcomes:
- Cognitive performance benefits are correlated with lower CO2 and particulate levels; teams think clearer and make better decisions in cleaner air environments.
- Wellbeing and morale translate into higher engagement and retention; the preference and happiness metrics in the study mirror what we see across high‑performing workplaces.
- Brand and customer impression: Living walls signal sustainability leadership and innovation the moment visitors step inside.
Implementation Guidance
The question is no longer “Do living walls work?” but “How do we design and run them so they keep working over time?” To harness the benefits demonstrated by Gensler:
- Assess your baseline indoor air quality. Deploy sensors for CO2, PM2.5, RH and TVOCs to understand current conditions and set targets that living walls can help meet or exceed.
- Design for performance. Specify species with proven capacity for particulate capture and CO2 impact; pair with efficient, low‑glare lighting that supports plant health without excessive heat.
- Integrate with building systems. Coordinate with HVAC to actively manage microclimates; consider localised ventilation strategies near installations.
- Plan for care. Build a maintenance protocol (irrigation, pruning, sensors, nutrient management) that ensures long‑term stability and odour control.
- Scale strategically. Favour distributed installations across floors and collaboration areas to maximise exposure and resilience; track outcomes and iterate based on data.
Gensler’s research validates what many progressive workplaces already suspect: living walls are powerful tools for healthier, happier, more resilient offices. With the right design, plant science and building systems integration, green walls can shift indoor air quality and employee experience from good to exceptional.



















