Passive Vents on a Hipped Roof
We recently had our roof replaced due to age and the roofer cut holes in our roof and installed passive vents. He did not tell me he was going to do this and it was not on the quote. I had previously consulted with a building science guy years ago about high temps in my attic and asked about venting. I have a heat pump and a down flow air handler in my attic along with R6 insulated ductwork and cellulose. It’s a low pitch hip roof on a brick Italianate home built in 1890. The building science guy explained to me that you don’t vent an attic to get rid of heat, you vent them to get rid of moisture (if you have a moisture problem). Since then, I was committed to NOT venting my attic space. When I discovered what the roofer had done, I confronted him about it and explained that I did not authorize him to do that. His response was that new shingle manufacturers won’t warranty a roof unless it is vented. My attic has averaged 73°F since April of this year and 43.8% RH with a high temp of 114°F and a low of 38.7°F. I am in zone 7a. I do not have any moisture problems that required venting. There are no soffit vents but it is not 100% sealed up there.Are the vents something that I should remove?
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What problem do you think the vents are or will cause?
Introducing moisture into the attic. I am watching my dew points very closely but I don't want condensation in my attic. With no soffit vents, the rooftop vents could draw moisture from inside my home into the attic. With a sealed attic and no vents, there is no air draw into the attic. No air draw = no moisture draw from anywhere. Plus, everything has been fine for over 100 years so why cut holes into a perfectly good roof?