So I know its pretty normal for a 91 civic to get condensation on the inside a bit..But mine has just recently went over the top. It froze last night and for the first time ever, I had to scrape the inside of my windshield because it was just as bad as the outside...What is this nonsense!

 

Get it resealed

 

My 91 hatch is doing the same thing.This is my fourth EF and I've had three CRXs and never had this problem.I did notice some wetness in the front passenger floorboard and a couple drips around the heater box under the dash.It's been cold here but going to be nice tomorrow so plan to check it out then,could be your heater core leaking but if you don't smell coolant then I don't know.I'll post my results up if I find anything.