Again your advice is the wrong advice for someone in Montreal in a winter climate who would see your absolute worst as a bad late spring day not worth remembering.thriftshopper wrote: ↑Jan 7th, 2019 8:28 pmCould be the humidity levels here. It's pretty much near saturation outside over the winter (or rather, monsoon season which is ~7-8 months a year) on most overcast/cloudy days (may drop to 80% on a sunny, clear day), and a fairly constant low 60% inside (not sure what it is inside the sunroom which is built over a patio above and adjacent to inhabited/heated space). RH is around 50-55% inside and out in dry season a.k.a. summer.
The current humidity issues come when the temperature drops (relatively) rapidly and overnight and there's a wind that chills the double-paned windows. RH at the surfaces climbs to 100% hence dew.
If you can tell me how to keep the sun room dry, I'm all ears.
Or in other words giving advice to someone with an EV on how to adjust their carburetor...
But you can go here and ask some building scientists about your situation