ERV system efficiency in tiny house
In the middle of our tiny house build and am trying to square away the ventilation system.
First, we are using the twinfresh comfo erv. The house is 200sq ft total. The ideal plan is to install the erv in the 26 sq foot bathroom directly facing the doorway (see picture) to act as a bathroom fan for moisture removal during shower, and then run otherwise continually to do its job at bringing in fresh air to the entire house.
I have several concerns/questions regarding this idea and am looking for any advice. First, is this erv adequate for moisture removal in the bathroom or is that totally far fetched? I have read that you need 1cfm per square foot of bathroom and the Twinfresh is 32 cfm on high. Is this enough or does the typical rule not apply because it is such a condensed space? We live in an extremely wet climate (the pacific northwest) so minimizing moisture to prevent mold growth is a concern.
Second concern is if the location and positioning of the erv will adequately reach the air of the whole space? See the picture to see how it is positioned.
Third concern is if we have a 160 cfm hood vent for the range, is the erv going to provide make up air at a fast enough rate that we won’t be constantly creating a negative pressure in the house that will be forcing air in through cracks?
I am wondering if it would be better to put an exhaust fan in the bathroom for moisture and put the erv in a different location to better reach the air in the whole house (see pictures for alternative locations). If we do this I’m wondering if the vacuum effect will be even more of an issue and if we need to install a separate vent for make up air.
We want to get the most out of the erv and put it in the most efficient spot, as well as manage moisture properly as I am very sensitive to mold and our area is susceptible to it.
I don’t know much about this so any thoughts are greatly appreciated!
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