We are building a new home and wish to include a rainwater catchment system. Are architectural shingles safe for watering food plants?

Asked by Alice Coblentz
Asheville, NC

We are also considering a baked-on-enamel metal roof as an alternative.


Kevin Holdridge

Answered by Kevin Holdridge

Charlotte, NC

KDH Residential Design, LLC

February 12, 2011

Asphalt shingles can leach chemicals such as zinc, lead, chromium, arsenic, and polyaromatic hydrocarbons.

  • It is not exact as to what the levels are or what levels would be safe for watering edible vegetation.
  • It's recommended that this collected water is only used for flowers and lawns, rather than herbs, vegetables and fruits.

An alternate roof material that would be suitable for reclaiming water for food plants would be a glazed tile or enameled steel.


For more information:

Read "Is it feasible to reuse greywater as irrigation water?", a Q&A answered by Randy Potter.

Tagged In: greywater

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