What is a good ventilation and dehumidification strategy for an existing home?
At some point soon I will complete the remodel on my new (old) townhouse.
This project involves a lot of updates, including improving air sealing and insulation, eliminating combustion devices, and installing two new high efficiency split systems (based on Manual J). Overall, the townhouse will be much tighter and more efficient when all the work is completed.
But I am wondering how to address ventilation and dehumidification.
I may be able to maintain a safe humidity level just with the new HVAC systems. And I may be able to ensure adequate ventilation with a supply-only approach.
My inclination is to install a few humidity monitors (in the attic and around the living space) and see what happens with moisture levels over the next few months. For ventilation, I am considering introducing 20 to 40 CFM of outdoor air and then checking for “stuffiness.” (My rough guess is the townhouse (2,800 square feet with two occupants) needs about 43 CFM.)
There seems to be a lot of debate about what “adequate ventilation” actually means. I don’t want to over- or under-ventilate. If necessary, I am comfortable with installing a dehumidifier/ventilator and/or a dehumidifier and an ERV.
If this was your project, what would you do?
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