Worst-Case Scenario: See what can happen to multiwall polycarbonate on less than 5º pitch
– Condensation will not effectively drain out of the sheet.
– Leaks at lower edge much more likely
– Capillary action will suck water up the channels
– Mold & mildew will gather, turn black and never go away
Worst case photo, heavy pollen, virtually no slope, never washed.