seam sealing in freezing weather

I live right down the valley from you and I always do my seam-sealing indoors in the winter. Do the seam-sealing in the morning, then go out for the day, then air out your apartment when you return. Most of the solvents will have evaporated within the first couple of hours so there really isn't such a big health risk. The air indoors is very dry during the winter, which slows down curing, so you might want to take a hot shower in the morning to get the humidity up, then hang the sealed item in the bathroom.