Roofing
When designing or implementing your system be sure to follow the principles for cistern systems described in Rainwater Harvesting for Drylands, Volume 1.
Metal Roofing
Be sure roofing is at least 26 gauge, since lighter gauges can dent. Baked-on enamel, galvanized, and galvalume steel roofs all work with water harvesting systems.
www.metalroofing.com
List of contractors, distributors, and manufacturers across the country.
Mueller, Inc.
Lap-style corrugated, U Panel, R Panel, and AP panel metal roofing.
www.MuellerInc.com
ASC Building Products
www.ascbp.com
Tucson
MasterCraft Metals, Inc.
Standing Seam Roofing
(800) 607-7468
(520) 792-2418
www.mastercraftmetals.com
Roof Ops Roof Options
Corrugated, Galvanized, Rusted, R Panel, Metal Tile, Metal Shingle
(520) 318-4364
Allied Building Products
(520) 795-7663
Elastomeric Paint Approved for Potable Rainwater Catchment Systems
The following have been tested and certified by the National Sanitation Foundation International (NSF) as approved potable-water-catchment coatings that comply with the requirements of NSF Protocol 151 “Health Effects from Rainwater Catchment System Components” (www.nsfconsumer.org/environment/rainwater.asp):
Weather Barrier Rain Coat 2000
An acrylic roof coating that can be applied over an existing roof of less-desirable materials such as asphalt shingles. Due to its light color it is also effective in passively cooling buildings. Manufactured by Finnaren & Haley Inc., Conshohocken, PA.
www.haleypaint.com/weatherbarrier/index.html
Topcoat W. O. B. White (without biocide)
A water-based liquid that can be applied with a brush, roll or spray mechanism. It cures to form a seamless rubber membrane that covers the entire roof. Topcoat W. O. B. White (without biocide) is manufactured by Topcoat, Inc. a subsidiary of GAF Materials, Inc., Walpole, MA. Note: Topcoat W.O.B. is produced in the Caribbean, and while readily available there, it can be difficult to obtain in the Continental United States.
(800) 669-4128
Vulkem 450/451 PWC and Vulkem 450/451 PWC Red
Elastomeric paints rolled or brushed onto a roof surface. According to a representative of the manufacturer the products are currently used in Bermuda and the Virgin Islands, but may be difficult to acquire within the continental United States. Manufactured by Tremco Incorporated, Mameco Manufacturing Division, Cleveland, OH.
(216) 752-4400
2001 Super-Flex 100% Acrylic Elastomer Roof Coating, 3000 Acrylic Barrier Coating, and TK2001 Elastomeric Finish
All 3 products are manufactured by the Scott Paint Company, Sarasota, FL.
(941) 371-0015
Environmental Liquid Membrane System (ELMS)
A USDA Certifiec Biobased Solar Reflective Soy Oil Polymer Roofing Material for Low Slope Roofing Assemblies
www.greenproducts.net/pages/elms50.html OR
www.greenproducts.net/pages/elmsplatinum.html
Tucson
MirrorSEAL
A continuous-filament, single-ply, fluid-applied roofing system. It is a non-petroleum-based polymer. Due to its white color it is very energy efficient in hot climates. It is soon to be tested by the National Sanitation Foundation International (NSF) to see if it is approved as a potable water catchment coating that complies with the requirements of NSF Protocol 151 “Health Effects from Rainwater Catchment System Components.” Currently it has been tested and certified by the FDA 175-300 as approved for Direct Food Contact. The EcoHood in Phoenix (AZ) has used it and is very pleased with its performance.
(520) 628-1553
http://www.innovativeformulations.com/mirror/index.html
Elastomeric Paint Not Yet Certified by Neutral Third Party for Potable Rainwater Catchment Systems
The manufacturers of the following products claim they are fine or are likely fine as a roof surface with potable rainwater catchment systems. However, the following products have not yet been certified by a neutral third party, such as NFS, as approved for potable rainwater catchment systems.
AMES Blue Max
A special blend of adhesive, high-strength elastomeric liquid rubber. It is a new impenetrable rubber technology for waterproofing in extreme wet situations such as flat roofs, below-grade foundations, basement walls, cisterns, water troughs, catch basins, ponds and fountains. Technicians for Sustainability uses it to seal the interior of their steel culvert tanks set in a concrete base. It can be ordered at many ACE Hardware locations. Notes: Water coming in contact with Blue Max can be expected to have a slight chemical flavor. Also, this product is not certified as such by NSF, but the manufacturers claim it is safe for use in potable rainwater catchment systems.
www.amesresearch.com/bluemax.htm
Safecoat Dynoflex RoofGuard Elastomeric Roof Coating
A water based, low odor roof coating suitable for properly primed roofs. The manufacturer has verified that this product is:
- Lead-free
- Mercury-free
- Cadmium-free
- Copper-free
- Antimony-free
This likely makes it a Living Building Challenge-compliant product. The Living Building Challenge is a Green Building Certification that goes well beyond LEED. The product is currently manufactured in Los Angeles, California, by American Formulating & Manufacturing.
www.afmsafecoat.com


