Soffit vents, but no ridge vent
Hi all, first post here. My wife and I bought a Craftsman home built in 1924 back in March of this year. Bristol TN, climate zone mixed humid. Turns out a 95 year old home is a handful for a pair of first time home buyers!
We just had a new roof installed and none too soon, it took 14 new sheets of OSB to get the decking back into shape.
The contractor deleted the old roof vents and added ridge vents to both the main ridge and the ridge on the “dormer” style room typical of the Craftsman style. So far so good. It already had soffit vents front and rear.
I was up in one of the attic spaces recently to work on some low voltage wiring and noticed that it doesn’t have any “outflow” venting. It has the soffit vents mentioned, but it’s an addition to the house and when the addition was done they simply built on top of the old roof at a reduced angle to extend the roof line. Where the two meet it’s sealed up. So the old soffit vents, if they exist, are under the old eaves inside the attic and the new roof section has soffit vents but no good way for air up in the cavity created between the old roof and the new to escape.
I’ve attached a quick sketch of the geometry. Red is the addition. Both sides of the house have venting at the eaves but where the red roof meets the green roof there’s no airflow.
I’m wondering is my best bet is to simply get a hole hog rental and pop a bunch of holes from the addition attic up to the original attic? Leave it alone? Spray foam the whole underside of the deck and seal it up, soffit vents included?
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