Last summer, we had our pitched roof replaced, it was about 20years old, some of the underlying wood also had to be replaced (water damaged from condensation inside the attic).
The roofer didn't think we needed a ridge vent, so they installed 3 mushroom vents with one equipped with a power fan. As well, we made sure all the soffit vents were clear of insulation (which prior to the roof being fixed, alot of the soffits were blocked by the insulation).
Now it's 6 months later, and almost all of the new wood has molding on it (spots), and some area have a pretty good patch of mold (non black mold). The roofer seems to think the mold came from the old wood that wasn't removed and has now traveled to the new wood. The roof has stood up to a good amount of rain without leakage (at least dripping), and the last snow seemed to make the wood wet, but which dried the next day (when the snow was gone).
Our crawl space usually doesn't have water, especially since we haven't had much rain, so I don't think it's moisture coming up from the crawl area. Our Bathroom does vent to the attic, but the wood near the bathroom area actually looks pretty good.
Does this sound more than just ventilation problems? Did we really need that ridge vent vs the mushroom vents?
Right now we are at the beginning, the roofing company isn't shrugging us off, but would like to get some objective opinoins. Realize it's difficult without actually viewing.