ATLANTA - The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) approved a change to its residential ventilation standard to encourage home retrofits to improve IAQ.
“With the U.S. economic stimulus having a great deal of focus on weatherization
and other residential retrofits, we developed this change to help improve
indoor air quality for public health and safety,” said Steven Emmerich,
Addendum e to ANSI/ASHRAE Standard 62.2-2007, Ventilation and Acceptable Indoor
Air Quality in Low-Rise Residential Buildings, allows alternative methods for
meeting the standard’s requirements regarding kitchen and bathroom exhaust
fans. The standard currently requires fans in those rooms.
“For new construction or renovation, it’s simple to meet those requirements,”
explained Max Sherman, former committee chair who now serves as consultant to
the committee. “But the committee recognizes that installation of fans can be a
barrier when added to existing homes in terms of expense and practicability.
For example, an interior bathroom with ceiling joists running the wrong way may
require ripping out a lot of ceiling and cutting studs to install
An example of an alternative compliance path that is allowed under the addendum
would be increasing the overall whole-house ventilation rate to compensate for
insufficient or nonexistent bathroom exhaust.
While the alternative path could result in modest increased energy use due to
the extra whole-house ventilation required, Emmerich noted that the proposal is
being made because experience has shown that people doing retrofits will often
ignore the standard if the fan requirements are too onerous. “This can lead to poor
indoor air quality,” he noted. “So while the preferred method is to have the
right-size exhaust fan, we are proposing this alternative.”
For more information, visit www.ashrae.org.