Skip to Content.
Sympa Menu

permaculture - [permaculture] Roofing materials and water collection

permaculture@lists.ibiblio.org

Subject: permaculture

List archive

Chronological Thread  
  • From: "Gene Monaco" <efmonaco@comcast.net>
  • To: <permaculture@lists.ibiblio.org>
  • Subject: [permaculture] Roofing materials and water collection
  • Date: Sat, 14 May 2011 20:31:17 -0400

Does anybody have any long-term experience with Galvalume.
I have three concerns and no answers:
1) Since it is 55% Aluminum-Zinc alloy-coated sheet steel, the aluminum
might leach into the water giving us Alzheimer's.
2) How does it weather over time. There are a lot of raggy looking metal
roofs out there. It might be good for a while, and I know that nothing
lasts forever, nor should it, but what does it look like after 20 years?
What happens as it deteriorates?
3) Seems like a lot of embodied energy (high carbon footprint). Aluminum
from far away...
-Gene

Date: Sat, 14 May 2011 07:57:13 +0100
From: harry byrne wykman <lists@peacetreepermaculture.com.au>
Subject: Re: [permaculture] Roofing materials and water collection
To: permaculture@lists.ibiblio.org
Message-ID: <20110514075713.59a55dbf@humilis>
Content-Type: text/plain; charset=UTF-8


Here's a quote from a write-up of a recent study:

Cockrell School faculty and students conducted an in-depth study --
recently published in the academic journal Water Research -examining
the effects of conventional and alternative roofing materials on the
quality of harvested rainwater. The study, led by civil, architectural
and environmental engineering Assistant Professor Mary Jo Kirisits,
showed that, of the five roofing materials tested, metal (specifically
Galvalume??), concrete tile and cool roofs produce the highest
harvested rainwater quality for indoor domestic use. The study also
showed that rainwater from asphalt fiberglass shingle roofs and
increasingly popular "green" roofs contain high levels of dissolved
organic carbon (DOC). Although other potential pollutants can be
significantly lower on green roofs (turbidity and aluminum), the high
DOCs are significant where these roofs would be used for potable
rainwater collection.

Source: Rainwater harvest study finds roofing material affects water
quality : www.sciencedaily.com

Harry
http://www.ptpc.com.au
*********************************************





Archive powered by MHonArc 2.6.24.

Top of Page