Improved Productivity Quantified

Following the release of The COGfx Study, which showed dramatic impacts of ventilation on cognitive function, the research team sought to evaluate the economic and environmental costs against the health and productivity benefits of enhanced ventilation in office buildings. Studying three ventilation strategies and four different heating, ventilating and air conditioning (HVAC) systems across seven U.S. cities, the team found that the indoor environment previously associated with a doubling of cognitive function test scores can be achieved at an energy cost between $14 and $40 per person per year and result in as much as a $6,500 equivalent in improved productivity per person per year. When energy-efficient technologies are utilized, the study found the energy costs to be between $1 and $18 per person per year, with a minimized environmental impact equivalent to approximately 0.03 cars on the road per building per year.

Improved Productivity Quantified

Doubling the ventilation for improved productivity costs between $14-40 / / year in all climate zones investigated


Energy-Efficient Technologies are utilized, the cost is between $1-18 / / year in all climate zones investigated

When Ventilation is Increased From


cubic feet per minute (CFM) of outdoor air per person


cubic feet per minute (CFM) of outdoor air per person

8 Percentile Increase

in employee decision-making performance

Improved Productivity Per Person Per Year


The increased productivity of an employee is more than

150× greater than

the resulting energy costs

On average, greenhouse gas emissions equivalent to


additional cars on the road / building / year

at the highest ventilation rate (40 CFM/person) with an energy recovery ventilator.

Three decades of research show the health benefits of increased ventilation, and now our recent research shows that these benefits extend to cognitive function, yet enhanced ventilation credits in green building certification systems are not uniformly pursued. We sought to understand potential barriers to widespread adoption.

This research suggests that the health and productivity benefits far outweigh energy costs and environmental impacts can be mitigated through a variety of readily available strategies. It is time we move away from ventilation designed for merely acceptable indoor air quality and move towards design for optimal indoor air quality. We have been presented with the false choice of energy efficiency or healthy indoor environments for too long. We can – and must – have both."

Dr. Joseph Allen

Assistant Professor of Exposure Assessment Science at the Harvard T.H. Chan School of Public Health, Director of the Healthy Buildings Program at the Center for Health and the Global Environment at Harvard Chan School, Principal Investigator for the study

Calculating the energy & environmental impact of increased ventilation for improved productivity

7 U.S. cities selected in various climate zones

  • Boise, ID
  • San Francisco, CA
  • Albuquerque, NM
  • Boston, MA
  • Baltimore, MD
  • Charlotte, NC
  • Austin, TX

Standard Office Building*

  • 53,000
    sq. ft.
  • 3-story
  • 268

4 HVAC System Strategies

  • Variable
    air volume
  • Variable
    air volume
    with energy recovery ventilator
  • Fan coil
  • Fan coil
    with energy recovery ventilator

3 Indoor Environments

  • 20 cubic feet per minute (cfm) of outdoor air per person
  • 27.6 cubic feet per minute (CFM) of outdoor air per person. 30% higher ventilation than ASHRAE Standard 62.1-2010, a U.S. Green Building Council LEED® credit requirement
  • 40cubic feet per minute (cfm) of outdoor air per person. Enhanced green environment from the cogfx study

Annual energy consumption

Used Carrier’s Hourly Analysis Program (HAP) to calculate in kWh, then converted to kBtu/year

Annual per building occupant energy costs

Average state utility prices for each city to estimate

Environmental Impacts

Derived using the Environmental Protection Agency’s Power Profiler Tool

It’s important to note that our study provides a conservative estimate of the benefits of enhanced ventilation because we focused solely on cognitive function. The public health literature indicates that we would expect many co-benefits of increasing ventilation rates, such as reduced absenteeism due to illness, which has clear impacts on productivity."

Piers MacNaughton
Doctoral Candidate at the Harvard T.H. Chan School of Public Health and project manager of The COGfx Study

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