While installing a phone extension in my mother-in-law's house, and working in the attic, I noticed ice on the inside of the roof plywood along with the roofing nails coated with ice. This only seems to be on the East side of the house. The house is a ranch with a hip roof, aluminum siding, normal roofing shingels (about 5 years old), and the house is located in central New Jersey. The house is about 22 years old, and my mother-in-law said that she remembers seeing the ice on the inside of the roof even before the new roof was added. The insulation is on the floor of the attic and is about 6 inches thick (fiberglass). I'm not sure what R value that is. Also, when the temperature goes above freezing, the ice starts to melt and drips on the fiberglass insulation. What can be done to eliminate the ice forming inside the attic?
Attic condensation comes from leakage from your living space into your attic. Look for leaks, areas where air can move into your attic. If you have severe leakage, more ventilation would make it worse, creating a greater negative pressure in your attic.