These comments refer to virtually all petroleum based (asphalt) roofs.
I would like to say that GAF is one of the finest manufacturers of roofing materials on earth. I've found them extremely professional. You will never go wrong having the GAF roof of your choice, and they are well represented, both corporate, and in the field.
This information is directly from GAF’s website, and I admire them for telling you the truth.
SUBJECT: Reclaimed Water From An Asphalt Shingle Roof
Q: Can I Reclaim Water (Collect Water For Use) Run-off From My Roof?
A: Yes… But you should only use this water for lawn, shrubbery, and flower irrigation since water run-off from asphalt shingles is not FDA approved for potable water reclamation or agricultural use.
What this means…is that because it is not FDA approved, the reclaimed water is not suitable for:
• drinking
• cooking
• bathing
• watering of fruits or vegetables for human consumption
Q: What Should I Know?
A: Water reclaimed from a shingle roof… may present a variety of hazards that may affect you or your animal’s health. While the water may seem “clean”, consider:
• Asphalt is processed from crude oil and there are chemicals in asphalt that can be hazardous to your health if consumed.
• The granule surface can collect dirt and other air pollutants which vary by location… water running over these granules can collect the dirt and pollutants as it runs off the roof.
• Under the correct conditions, algae, mold, moss, and mildew can grow on the shingle surface. These fungi may be harmful to people and animals when introduced into a drinking water supply.
• Shingles may contain copper oxide, or other algae inhibitors that may harm aquatic life.
Please let me state that GAF is the largest manufacturer of roofing materials on earth. But we never consider the “lowly roof” which I happen to think is the most important component of any structure.
"If rainwater harvesting were used in only 15% of landscape irrigation in the U.S. that would equate to over 1 Billion Gallons of water saved EVERYDAY. Come learn how different technologies turn into LEED points, offering your clients the most cost effective and water efficient solutions available, adding value to your firm and proposals. Water conservation has become a necessary element to most new development projects. A roof area of 1,000 square feet w one inch of rain equals over 600 gallons of pristine water! Rain is a perfectly pure source of water that is inexhaustible, no matter where you live.
An average home uses 40%-60% of its water for landscape irrigation. Harvesting rainwater can reduce your overall water consumption by replacing the source from municipal water to rain water. Imagine watering your small garden with pure natural rainwater". (Courtesy: USGBC)
I was primarily thinking of the millions of people on earth who do not have accesss to fresh water, other than roof water catchment devices. Over a million in Australia alone, 400,000 in New Zealand, and the list goes on and on.
I think we should consider a broader scope of people than just those immediately around us. I'm doing my very best to spread awareness of fresh water, and how to collect it with less contamination.
Looks like nobody's interested in Iceland, and their source of power, but it's really quite a fascinating example of using resources that are readily available. 97% of their energy demand is by geothermal in case you were wondering.
Most metal, tile, and Thermoplastic Polyolefin (TPO) membranes are your very best method of collecting cleaner water. If a shingle manufacturer tells you not to do it, I would suggest you follow that advice.
Thank you to my friends around the globe, and know I'm working hard on your behalf to make things better for ALL people.
I never cease to be amazed by the people in so many countries that visit with me, and you are most welcomed here. If you have specific topics, or projects you think I may assist you with, simply send your request to my central email address: RobertRSolomon@aol.com
Again, I am thankful, and want you to smile, be happy, and always remember to keep looking "UP".
Robert R. "Ron" Solomon
CCC1325620