Roofing material for water catchment
Hello,
I am designing a water catchment for my zone 6 coastal maine house. Its a 3/12 single pitch roof. The roof can only be viewed by the squirrels, as it sheds towards a mature forest, so the way it looks is not a concern.
I will be drinking this water (filters, etc.) The main criteria in my decision are cost, contaminants from the material getting into my drinking supply, and penetrations.
I have narrowed my choice down to EPDM rubber roof and a metal roof. I will be installing it myself and there is a local metal supplier who is very inexpensive. Many penetrations in this roof, including a wood stove pipe. I am told that cinders are not a concern with EPDM.
I can get non standing seam metal roof for about half the price as standing seam.
Thanks for any input.
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Replies
stephenr,
From Chuck Bickford's blog a couple of days ago:
"The quality of the water collected depends in part on the roofing material. In this rainwater-harvesting document prepared by the EPA, wood, copper, painted, or lead-flashed roofs aren’t recommended for harvesting because the water tends to leach out harmful substances from those materials. Unpainted Galvalume or rubber membranes are generally considered to be the best for water quality."
https://www.greenbuildingadvisor.com/article/residential-rainwater-harvesting