Is closed-cell foam -- sprayed in -- OK to use for an entire house in southeastern PA?
We use an air to air heat exchanger. Will humidity be a problem? This is a single story, new build.
Humidity should not be an issue if you properly use your bathroom fans and kitchen fans.
A properly sized kitchen fan should run while you are cooking, and the bathroom fan should run not only during your shower, but for at least 15 minutes afterward. This is one reason why I spec and install a 15- to 30-minute timer for all bathroom fans, instead of leaving it on a single switch or tied into a light switch.
One other item: your ERV or HRV should be set up separately from your HVAC. One main reason for this is that no one knows how you will use your HVAC system and it may not pull in enough fresh air to properly eliminate the dirty inside air.
In the rare instance that humidity is an issue, I would first run a dehumidifier and then try finding the cause of it so you can eliminate the problem.
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