(Podcast) Drying Stuff vs. Drying Air - Humidification, Dehumidification, and Ventilation

This episode is a rebroadcast of a very useful episode from the Corbett Lunsford's Building Performance Podcast at buildingperformancepodcast.com/. Corbett talks to building moisture control expert Lew Herriman about moisture, ventilation, and what happens when you're drying "stuff."
When we think about humidity control, we have to ask if we're drying air or drying "stuff." Dehumidification is about drying the air, but many people think about it when they actually want to dry "stuff" like fabrics and other absorptive surfaces often found in residential applications. However, drying out "stuff" does affect how we would dry out the air.
Commercial buildings often don't have a lot of absorptive materials, as many have tile floors. Residences tend to have carpet and upholstery, making them challenging cases in building performance. The HVAC system controls moisture, whether they have a humidifier, dehumidifier, or neither. HVAC systems create pressure differences, which contribute to dry air infiltration. Homes heated solely by radiant heat would not be as good at drying the air, but good ventilation could supplement radiant heat.
When we have humidity control problems that affect comfort or moisture on absorptive surfaces, we might start thinking about controlling absolute humidity. Absolute humidity refers to the actual moisture content in the air, not the moisture relative to the temperature. However, most homes don't have the ventilation systems that would help dilute the humidity, including HRVs.
Then, when drying "stuff," you have to put heat in to get the moisture out.
Corbett and Lew also discuss:
Absolute vs. relative humidity
Dry-bulb temperature changes and dew point
Duct leakage
HVAC and building performance strategies for mixed climates
Energy-recovery ventilators (ERVs) vs. heat-recovery ventilators (HRVs)
Exhaust at the source
Dehumidifiers
Dehumidifying incoming fresh air
Hypothetical makeup air systems for residential applications
Comfort metrics
Learn more about Corbett's work at buildingperformanceworkshop.com.
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[@chickedwin7194]

Great

[@tubulartuber]

at 33:00 is he basically talking about a small heat pump based ERV?

[@mcmaestro9443]

I know this a old podcast but does the echobee thermostat solve some of these issues?