I had a new roof and vinyl siding put on my 34x24' 30 year old hip roofed colonial. The original roof had aluminum ridge vent and continuous aluminum soffit vents. The contractor installed perforated vinyl soffit vents- As best I can tell they are 5.9" per square foot net free vent air(NVFA)- the issue is they are only 4" wide per linear foot.
I told him at the time of installation they did not look like they were going to provide anywhere near as much air as the aluminum vents that they were replacing, but at the time I did not take the time to learn the engineering associated with attic ventilation.
The ridge is only 8 feet long and in the best case provides 144 sq-in of NFVA.
My attic is now 145F on warm summer days.
My best estimate is the perforated vinyl soffit vent is only providing about 200 NFVA. My estimate is the original aluminum soffit vent was providing about 550 NFVA
The contractor is recommending an roof fan.
I'm leaning to push him to replace the perforated vinyl with a vinyl or pvc product that would provide the original 550 NFVA.
As best I can tell he did not do ANY calculations before choosing the perforated vinyl soffits.
What would the experts recommend?
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