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I have a Lindal Sun Room with an R30 roof system comprised of 2X6 tongue and grove with 4 ” rigid foam on top. Lindal than has a system that suspends the roof sheathing about 3″ above that. That air space allows cold air to circulate over the top of the rigid foam insulation. On two or three occassions we have had severe incidents of the inside roof raining on us.
We live in the Chicago Area and the problem surfaced in late December and has not occurred since than.
The ridge vent is aluminum provided by Lindal and the builder is going to replace it with a “cobra”.
Any thoughts on what may be doing this?
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Prescriptive codes don't address the connection at less common angles, so base the connection off more typical ones using bolts, structural screws, blocking, and steel tension ties.
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Tell him you're afraid of snakes. CobraVent is a
Scouring Pad type material, and has not prevented rain and or snow from entering many a home I've seen. Baffled ridge vents have kept the rain and snow out. Others will argue, the more open the ridge vent is, the better the draft, and a positive outflow will prevent entraining of rain or snow... not so far as I've seen.
I'd be interested in hearing what FREDDY LU has to recommend with your Lindal System.
*Ed,I assume you're not talking about real rain from outside blowing in, rather, condensation induced rain. From where does the roof rain eminate? All over, or specific locations? Where there are joints in the rigid foam? What is the roof construction above the rigid foam composed of? Steve
*Ed. What you have is a ventilated insulated roof panel. the ventilation in question is to ventilate the underside of the shingles.You have no attic so what else could the vent be for? However, notwithstanding the claims of shingle manufacturers, it makes no difference in the longevity of the shingles. So remove the metal ridge vent and seal the opening. I'm still trying to understand how the "rain"is getting through the tongue and groove 2x6s? George's points are well taken.Gene L.
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Steve,
The problem is that warm moist air froze somewhere in the roof system, thawed, turned into water ran down and leaked through the 2x6's, alongside the rafters, etc. Had water dripping down in maybe 12-18 locations. Builder thinks it may have been the warm moist air seeping up through the ridge area, than freezing and at a later point condensing. They are guessing.
Cannot simply remove the ridge vent and cover it. There would be no air flow at all between the wafer board and rigid foam.
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I have a Lindal Sun Room with an R30 roof system comprised of 2X6 tongue and grove with 4 " rigid foam on top. Lindal than has a system that suspends the roof sheathing about 3" above that. That air space allows cold air to circulate over the top of the rigid foam insulation. On two or three occassions we have had severe incidents of the inside roof raining on us.
We live in the Chicago Area and the problem surfaced in late December and has not occurred since than.
The ridge vent is aluminum provided by Lindal and the builder is going to replace it with a "cobra".
Any thoughts on what may be doing this?