condensation in trusses

I installed a metal roof in 2013 and have experienced leaking through my ceiling the past couple of winters, usually after a cold snap of 0 or below 0 temps. The day it would warm up to say, around 30 or 35 degrees I'd have dripping. The amount of dripping would be directly related to how long the cold lasted - if a week or more, it would drip more than if it was cold for only a day or two.. I have proper venting in the soffit, with plenty of ventilation there, but where I think my problem lies is the versa vent I installed on the underside of my metal ridge cap. Uncompressed, the foam vent is roughly an inch and a half thick, but when I screwed the cap to the rib on the roofing this compressed the foam vent down to about 1/4 or 3/8 of an inch. Doesn't this restrict the airflow through the vent? The thought crossed my mind when I was installing it, but the directions on the box were clear that it would vent properly. There are no gable vents on the side of the house. I cut a hole in the drywall to take a peek, and the underside of the roof was sweating (this was just a couple days after the cold snap ended). I have no attic, they are scissor trusses. Also, the leaking occurs only at the ends of the length of the addition, roughly 8-10' on either end of a 36' addtition. I installed R-49 faced batts and the house structure is a basic roof, 10/12 pitch, no dormers or fancy architecture.		Norm Raapana 1/25/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20946/find/
It does not sound like the ridge vent should have compressed that much. What sort of attic vents do you have for intake?		Todd Miller Isaiah Industries, Inc. 1/25/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20947/find/
the roofing panels I have are ABC Roofing's Rugged Rib, which are low-profile, they only are about 3/8 high. The ridge is screwed down onto these ribs, thus compressing the foam. Should I have not screwed them so tight? I installed proper vents, about 11/2 inches of ventilation that extend into the ventilated soffit, then up into the trusses		Norm Raapana 1/25/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20948/find/
Thanks. It sounds like you have adequate intake. I have never worked with that kind of ridge vent so I would suggest contacting the manufacturer. But I wonder too if it should not have been screwed so tightly.		Todd Miller Isaiah Industries, Inc. 1/25/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20949/find/
Thanks Todd. I did contact the manufacturer, of course they said it will breathe and that is not the problem. I've thought of taking it off, installing those contoured foam strips over the metal ribs, then using some other vent, but not sure what type.		Norm Raapana 1/25/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20950/find/

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