Is it poor ventilation or heat getting into attic causing mold in attic?
We had a lot of mold in the attic. Dilapidated plywood. Ice damns. Drywall damage. Insurance wouldn’t pay, said poor ventilation. We replaced the roof (it was only 9 years old), replaced all the ply, had edge vents installed everywhere as well as new ridge vents.(not enough over hang to add soffit vents across the front of the house). Replaced all the rolled insulation (it was soaking wet) and added fiberglass blow in on top of rolled to R49. Bathroom vents were then vented out the roof. 1 1/2 years later we have huge icicles so we climbed up in the attic to see why and found mold all over the place again. Mold company came back out and said poor ventilation. Originally he only baffled every other joist along the edge vent and we asked him to baffle every joist. Roofer came out and said once he baffles every joist the ventilation should be good because he cut down intake in 1/2 by doing every other. Mold guy won’t eradicate until we figure out what the problem is.He said his baffling is not the problem. Brought a licensed builder with him who also said ventilation. He suggested widening ridge vent (he said currently it’s only 1inch wide and also said maybe Ventsure (OC) may not be a good ridge vent.
1-What do you think about ridge opening?
When you climb into attic there is a plywood inner wall nailed to the joists covering about 1/2 the front of the house. The attic in front of this wall is clean. That area also has it’s own ridge and edge vents.
2-Could that angled plywood wall be cutting off any circulation into the attic? All parties dismissed this idea. We have not air sealed and we don’t have a lot of things (can lights, electrical, duct work) running through the attic.
3-Can heat still be getting into attic with all the additional insulation?We are going crazy trying to solve this expensive puzzle. Also, we turned off the furnace humidifier. House is 3000 sf and this is the upper attic only over 4 bedrooms and 2 baths, not over the family room. Any advice?
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