My house is one half of a prefab duplex from the 80's. Last week I went into the attic and found mold covering the roof sheathing. It had not been there a few weeks earlier. The attic is supposed to be vented by soffit vents and ridge vent, but I found that the air is not flowing up from the soffit to the ridge like it should. The only moving air in the attic is the air blowing in from the ridge vent. The soffits are blocked by fiberglass batts and an additional layer of blown in insulation. So there's practically no ventilation.
Now here's the problem: the roof pitch is something like 2/12 and the rafters (except those at the soffit vent) run parallel to the ridge. The pitch is so shallow that I can't get any closer than maybe 10 feet away from the soffit vent from inside the attic. I can't clear out the insulation blocking the vents. Plus, if I did remove the insulation, the ceilings of the rooms below would be exposed and uninsulated for a couple of feet from the outside wall.
I'm considering buying an electric attic fan and just forgetting the soffit vent. Any ideas?