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I have a wood-framed, aluminum-covered patio cover that is very mildewed on the underside. On damp, cold nights there is so much condensation under there it’s like rain. I suspect that what’s happening is the aluminum is such a good conductor of cold that when it gets chilled, the warmer air on the underside gets condensed. I have not seen this happen on fiberglass covered patios. There is plenty of circulation – two sides are wide open. To fix it I may tear off the aluminum and put down plywood, paint the underside, and then roof with aluminum, steel, or fiberglass. The pitch is about 1″ per foot, so I think shingles are out, and the topside isn’t really visible anyway. Or plywood nailed to the underside framing? That may insulate the underside of the metal from the warmer air underneath, and I get to avoid re-roofing, along with prepping and painting the badly mildewed framing and exposed aluminum. Anyone have ideas? Gary Hastings
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I have a wood-framed, aluminum-covered patio cover that is very mildewed on the underside. On damp, cold nights there is so much condensation under there it's like rain. I suspect that what's happening is the aluminum is such a good conductor of cold that when it gets chilled, the warmer air on the underside gets condensed. I have not seen this happen on fiberglass covered patios. There is plenty of circulation - two sides are wide open. To fix it I may tear off the aluminum and put down plywood, paint the underside, and then roof with aluminum, steel, or fiberglass. The pitch is about 1" per foot, so I think shingles are out, and the topside isn't really visible anyway. Or plywood nailed to the underside framing? That may insulate the underside of the metal from the warmer air underneath, and I get to avoid re-roofing, along with prepping and painting the badly mildewed framing and exposed aluminum. Anyone have ideas? Gary Hastings