Baseline Indoor Air Quality Field Study in Occupied New U.S. Homes: Hot-Humid and Mixed-Humid Climates

Building America Team: University of Central Florida

Indoor air quality system outside.

This project is part of a national study aimed at characterizing indoor air quality in occupied homes. The homes will be up to current energy codes and researchers will closely monitor the use and performance of mechanical ventilation systems in those homes. Indoor and outdoor air will be sampled for formaldehyde, nitrogen oxides, carbon dioxide, and particulates as part of the indoor air quality characterization.

Research will include:

  • Measuring time-integrated and temporal profiles of humidity and contaminants of concern, monitoring the use of ventilation equipment, and tracking activities impacting pollutant emissions
  • Characterizing the prevalence, type, and installed performance of mechanical ventilation equipment in new homes; exploring regional variations in system designs and performance
  • Investigating associations of indoor humidity and contaminant levels with the presence of control measures, including ASHRAE 62.2-compliant mechanical ventilation
  • Targeting one week of data collection in 64 homes total; 32 per climate zone: 16 with and 16 without whole-house mechanical ventilation. Second week of data collection performed in 8 of the whole-house ventilation homes.

A national study characterizing indoor air quality in occupied homes includes monitoring of mechanical ventilation systems and testing for formaldehyde, nitrogen oxides, carbon dioxide, and particulates within homes in hot-humid and mixed-humid climates.

Southeastern U.S. whole-house ventilation characterization results:

  • In first 22 homes with whole-home ventilation systems, only 7 were operating upon arrival
    • 5 Energy Recovery Ventilation
    • 2 Central Fan Integrated Supply
  • 15 of the 22 systems were turned off by homeowners, contractors, or could not be made to operate due to non-functioning components
    • 7 capable of operating but turned off
    • 8 non-functioning
    • Most exhaust systems were operational, but none had labeled switches
      • A few had a sone rating > 1
  • In most homes, at least one range hood setting delivered 100 cfm
  • In more than half of the homes, at least one bath fan did not deliver 50 cfm.