One or Two ERVs ?
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I’m wondering what peoples experiences are with stand alone ERVs and how many are required to service a larger home?
Our current home has the ERV attached to the furnace with separate exhaust fans in the washrooms and laundry as you might expect for a standard home. However we’re planning a new build that will be very tight so I’d prefer not to have bathroom exhaust fans that would cause negative pressure in a tight home. The home is quite large with 3 washrooms upstairs, a powder on the main, as well as a guest room and powder in the basement. So 4 full washrooms and 2 half in total. Plus kitchen and laundry. There are 4 bedrooms upstairs and a guest room in he basement. About 4100 sqft above grade.
I see high performance homes online with similar counts that have one stand alone ERV. But also read that a single ERV doesn’t have enough CFM to support this many rooms so you really require 2 of them. Which of course is more cost. I’m wondering what people’s experience is and if there’s a best practice? We don’t have an unlimited budget so I’m trying to balance performance vs cost.
Thanks!
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Replies
Two units are twice as much maintenance down the road, so always try to get one unit to work.
If the capacity of the unit on boost is not enough for all the bathrooms (make sure to also include the exhaust for the kitchen area, laundry room and the basement/crawlspace ), you can connect the ERV to the most used bathrooms and use standard exhaust fans for the remainder. Since these will barely be used, depressurizing a house that big is not an issue.