Using Bathroom Vents for Whole House Ventilation
Hi all, I’m a little confused about the concept of running bathroom vents on timers to satisfy the required CFM for whole house ventilation. Even with evenly distributed bathrooms, does this strategy actually work to adequately change the air in the whole house? I would imagine that each bathroom would just suck in air from whatever cracks may be around each bathroom and keep the rest of the living spaces and bedrooms with stale/uncirculated air. Have tests been done on this concept to show that most rooms can get proper air changes without needing to vent each room or install an HRV/ERV?
I would really like to employ the bathroom vent strategy but I just want to make sure the concept works on some level for the whole house.
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Replies
SSB,
The type of ventilation system you are talking about is called an exhaust-only ventilation system.
For more information, see these two articles:
"Revisiting Ventilation"
"Ensuring Fresh Air in Bedrooms"
In the first of these two articles, I wrote, "Most ventilation experts discourage the use of exhaust-only ventilation systems, because these systems do a relatively poor job of distributing fresh air. (With an exhaust-only system, fresh air enters the house through random cracks in the building envelope. That means that homeowners can never be sure which rooms will get the most fresh air.)"