Mositure in Attic

I live in upstate NY. The temp. is around 10 to 15 degrees. with a windchill of about 0 degrees. Why is the wood all wet when I go int of the attic? Also the drywall and ceiling in my second floor are wet. We have ventilation in the attic. There is plenty of air moving around up there, I can see daylight from the ridge vent. The baffles for the soffit vent or are installed. A little background. I have had ventilation issues in he past from the home not being ventilated properly by the builder. There was mold growth up in the attic, and the shingles are starting to curl all over the roof. Since they corrected the ventilation issues. But it went about 4 years with no ventilation up there. Thank you all for your help and advice. I have learned much from your experience and expertise.