Standing seam roofs & rainwater harvesting
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For our new modern-design home, I’ve been contemplating a Galvalume (aka Zinc-Alume) standing seam metal roof. However, I’m wondering if there are any issues with harvesting rainwater from this type of roof (rather than from a painted standing seam metal roof).
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Replies
I would recommend using pre-painted galvalume and repaint as necessary.
A Texas study of roofwater contamination showed significantly higher levels of zinc and lead from a galvalume roof compared to an asphalt shingled roof.