Cost-benefit analysis of improved air quality in an office building

The study presents a cost analysis including energy calculations for three outdoor climates (cold, moderate and hot) to improve indoor air quality in an existing building considering both variable air volume (VAV) and constant air volume (CAV) systems with heat recovery. The study also simulates different indoor air quality levels due to different airflows of outdoor air. Considering previous studies data to rate the productivity impact of these levels, the annual benefit due to improved air quality was always at least 10 times higher than the increase in annual energy and maintenance costs. The payback time of the HVAC first costs involved in improving the air quality was always less than 4 months.