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<td>Metal Roofs</td>
 
<td>Metal Roofs</td>
 
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*Runoff may contain high levels of zinc, copper, and lead (see Table 5)</td>
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*Runoff may contain high levels of zinc, copper, and lead (see [http://stormwater.pca.state.mn.us/index.php/Typical_Annual_and_Snowmelt_Urban_Stormwater_Quality_Characteristics here])</td>
 
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Revision as of 15:10, 2 November 2016

Common roofing materials and water quality considerations
Link to this table

Roofing Material Water Quality Considerations
Metal Roofs
  • Runoff may contain high levels of zinc, copper, and lead (see here)
Sheet Roofing (PVC)
  • Recommended for non-potable use only
Tile roofs (clay, ceramic, cement, fiberglass)
  • Need periodic cleaning - debris may accumulate between tiles
  • Recommended for non-potable use only
Shingles
  • asphalt
  • composite
  • three tab asphalt
  • Recommended for non-potable use only
  • Some shingles manufactured prior to 1980 may contain asbestos in trace amounts
  • May not be suitable for irrigation if shingles have been treated for mold eradication or with herbicides
Shingles – cedar shakes/wood shingles
  • Recommended for irrigation only
  • Shingles retain moisture, support mold, algae, and insects, may be treated with fire retardant or other chemicals