Subject: [permaculture] Roofing materials and water collection
Date: Fri, 13 May 2011 17:49:58 -0600
We have a small building which is going to be roofed, and I am in the
middle of choosing a roofing material. I would like to keep the option
of collecting roof runoff open, and keep the roof as fireproof as
possible. Those are the primary concerns for this choice of roof.
I have heard/read the negatives about using water which came off asphalt
shingle roofs, so those are probably not an option. That would seem to
leave only a few choices:
Ceramic tile roofs are out, due to their weight and structural concerns.
Galvanized metal roofing seems like the best choice perhaps, for easy of
use, fireproof-ness, and runoff quality (as far as I have heard).
Another potential option is painted metal roofing (usually available in
wider sheets than the plain galvanized, and longer lasting. Only problem
is no manufacture seems to have any data about runoff water quality from
their painted roof materials.
I was wondering what people thought about these options; If there are
any others which I've missed; and if anyone had any hard data on
painted metal roofing leaching whatever into the water runoff.