When an ERV/HRV dies, won’t homeowners be poisoned?
ENGR_GC
| Posted in Energy Efficiency and Durability on
Here is my concern about “build tight, ventilate right”:
A homebuilder builds a “tight” house ( for argument’s sake 1.5 ACH 50). To “ventilate right” he installs a “builder grade” HRV or ERV that lasts 5-10 years. Then it burns out. The homeowner is my mother in law who knows nothing about houses or building science. She didn’t even know she had a ventilation fan and she wont’ know to replace it. Or perhaps she can’t afford to replace the ERV/HRV.
Will indoor air pollution accumulate in the “tight” house without ventilation and harm the occupants?
Thanks in advance!!
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Replies
Randy,
Millions of Americans already live in underventilated houses. Sometimes the occupants notice, and sometimes they don't. The situation isn't fatal.
Whether we like it or not, ventilation rates will always be under the control of the occupants. Some occupants underventilate deliberately, while others underventilate accidentally.
If the house has no mechanical ventilation equipment, the answer to underventilation is to open a window. Some occupants (if given that advice) will comply; others won't.
If a house has mechanical ventilation equipment, the answer to underventilation is to increase the ventilation rate, or repair the equipment if it is broken.
Here are the signs of underventilation: moisture on the interior of the windows during the winter, and smelly bedrooms. If your mother-in-law has those problems, she should increase the ventilation rate. If she doesn't, don't worry.
Randy,
For more information on this topic, see Ventilation Rates and Human Health.
Maybe homes really should have a dashboard, and HRV failure would be one of the "check engine" lights.
It should be "build tight and right, ventilate right". If low/no emitting building products are used, there should be no harmful off-gassing way before 5 years.