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Rainwater Harvesting

Rainwater harvesting using Magna-Loc roof panels at the Safari School in Phoenix, AZ

Water is a critical natural resource, and is essential for human survival. Efficient use of water is a core part of every sustainability program. In addition to water conservation, there is a growing awareness to manage our water supply for environmental and economic reasons. It's not surprising, then, that rooftop rainwater capture is gaining renewed interest.  

Rainwater harvesting is the collection, storage and use of rainwater. Rainwater harvesting system engineers prefer metal roofs over other options for several reasons and especially for potable water harvesting systems that have more stringent requirements. Engineers prefer metal’s slick surface that makes it easier to keep clean of dust and debris, as opposed to wood and asphalt shingles and tar and gravel roofs, which can hold and harbor pathogens. While clay and concrete tile roofs are also viable options, the porous natures of these materials create a danger for bacterial growth, and can cause the loss of as much as a 10 percent of water from inefficient flow and evaporation.1

To learn more about rainwater harvesting for home or business, visit American Rainwater Catchment Systems Association,

1"Metal Roofs Provide an Ideal Platform for Rainwater Capture" (MetalMag, February 2010)

*Note: Please check with your local jurisdiction about the laws in your area governing rainwater collection/harvesting. See for a list of states that allow for rainwater harvesting and how the collected water can be used. The collection of water for drinking purposes is regulated by the EPA under the ‘Safe Drinking Water Act’. The EPA’s authority is ceded to the National Sanitation Foundation (NSF), a nongovernmental advisory organization, which can be found at