Oh..that's a 'Coating Flap'...

[Marc Morin]

I called out this dryer duct rooftop vent being taped over at it’s sides which inhibits the discharge of exhaust and presents a 180-degree bend. The roofer responded that it in fact was not taped over...but provided a 'coating flap' to prevent wind driven rain from entering. I've seen 10,000+ roof vents and none were ever taped over so I'm thinking this particular roof (and only this roof) is prone to severe wind in wet conditions. Are they kidding?

[Jerry Peck]

Not sure of what is shown, but from what I think I am seeing, that did not start out as a proper dryer exhaust vent and it certainly has not ended up as one either.

[Marc Morin]

Exactly...but they're standing by the 'coating flap'! Ha!