Will ShingleVent II plastic ridge vent blow off at the very edge of the roof?
Properly installed there should be no concerns about ShingleVent II being pulled off the roof by the wind at any location on the roof.
ShingleVent II has been subjected to wind uplift testing. This test simulates a condition that is trying to pull the ridge vent up from the roof deck. ShingleVent II was rated at 360 pounds per square foot because the test could go no higher. A 110 mph wind is considered to provide wind uplift force of 90 pounds per square foot. Therefore, properly installed there should be no concerns about ShingleVent II being pulled off the roof by the wind at any location of the roof (middle of the roof or edge).