Add ventilation to old attic?
I’ve read several of the blogs and articles regarding attic ventilation on this site and have searched through the Q&A section. I’ve learned quite a bit but am still a novice, and I haven’t quite found the answer to my specific question.
I purchased a 1912 Victorian about a year ago in southwest Ohio (climate zone 4A) and have slowly been making long-needed maintenance repairs and updates. Years ago the third floor attic was framed and converted to living space. There is zero insulation behind the knee walls, along the roofline, or in the ceiling steeple above – and no insulation I can see in the old attic floor (between he second and third stories). Additionally, there are no vents in place of any kind. Needless to say, the temperature up there quite mirrors outdoor temperatures despite meager attempts otherwise with baseboard heaters and window AC units.
We have no ductwork behind the knee walls, and while hot, the space feels dry and has not had any mold issues evident.
I found a reputable insulation contractor who will place fiberglass insulation and a radiant barrier along the knee walls and attic ceiling (and will blow fiberglass insulation along the roofline between) – at a seemingly appropriate R value for the climate.
My question relates to attic ventilation. He recommended talking with a roofer about adding some ventilation to the space – and that roofer recommended several box vents. I’m not in a financial position to re-do my roof yet (to add ridge and soffit ventilation if needed), though the roof is nearing the end of its life. From what I’ve read, I’m not sure box vents will do much, if at all. Nevertheless, should I add some ventilation to that space? Is there a risk to adding formal ventilation to a space that has been without for 106 years? Does adding insulation change the equation?
Thanks for reading and for any insight you can provide.
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