Is cooling adequate via natural ventilation?
There was a lot of interest in natural ventilation I saw a while ago. Some people think this can also cool a house. Was this always a confusion of two separate goals and physics? What is the thinking today?
I am in a hot humid summer / cold winter climate.
The premise in summer is to seal the house to keep out heat in the day and open all the windows at night when the air temperature drops. Problems with this idea:
1. Would like house to be 75 F with 50% R.H. but the air temperature at night is also warm, 65 to 75 F and the R.H. is 65 to 80%. This drives very little to no air movement via stack effect. Stack effect in winter when the outside is at -10 to +30 F is a lot greater.
So there may be enough air flow for ventilation but not for significant or any cooling.
2. Outdoor humidity is high, and R.H. is even higher at night if the air has cooled from 90 to 70 in a few hours. You are bringing humidity into the house and reducing comfort. Even cooler air at 80% R.H. isn’t going to make you feel any cooler.
I can see natural cooling working okay in shoulder months when nights are cooler but not when it is needed the most.
PS I think climate change is partially responsible. Old notions / rules of thumb die hard.
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