I have a home about 30 years old that I purchased about 1 1/2 years ago and the portion of the house that was originally the garage was converted into a living space about 20 years ago from what I gather from neighbors. There seems to be an issue with the ceiling in this area getting what look like water spots. I peeled away the paint and drywall in one spot but it does not appear to be wet at this point. The spots appeared just as we were getting into the colder weather and we started using the heat...could these spots be condensation where there is not a full ceiling and the insullation looks like a later of the styrofoam. I have attached a couple pics and you can see the nails have spots and along the front edge of the roof. I don't want to fix and have it all happen again. Might be just as easy of spraying a coating of one of the rubber type crack repair products on before painting to keep the moisture from coming through. Any thoughts or comments are appreciated.
Go into the area above this room and check it out. If you need to open an access hole, do it. There should be one available for periodic inspection.
The dark spots probably coincide with nails or screws in the ceiling. They get very cold, the warm air from the room gets them damp and dirt clings to them. The area along the wall has gotten wet.
The issue could be a lack of insulation, a lack of ventilation, ice damming, a small roof leak, etc....
What does the roof look like from the outside?
Is there frost on the nails penetrating the roof?