I have noticed dark lines on the ceilings in my home that define where the trusses are in my roof. A roofer who inspected my roof told me I have condensation in my roof & that I needed to have triangle vents installed at each pitch of my roof & a Whirly Bird Vent. The Insulation guy told me the roofer doesn't know what he's talking about & that the problem is I don't have enough insulation in my roof-he never inspected my roof. I am single there is not excess water used in my home, I don't use any type of space heater, no fireplace, etc. I keep my thermostat set at 66 in the winter months and rarely run my AC in the summer. I am very scared because any research I've done seems to suggest my soffit vents are blocked and that my roof is not venting properly, but no one seems to agree. They all have numerous different "thoughts" but I need an honest answer. I'm desperate that if I don't have this corrected the problem could progress. The house was built in 2005, and does have a dry basement. Please help!