20/05/2026
This is a rooftop exhaust vent cap (specifically a gravity or static ventilator), designed to allow hot air, fumes, or gases to escape from a building's ventilation system while protecting the ductwork from weather and pests.
Here is a breakdown of its main components:
Square Weather Cap (Top): The large, flat steel lid prevents rainwater, snow, and debris from entering the vertical ventilation shaft directly from above.
Wire Mesh / Bird Screen (Middle): The wire grid around the collar allows air to flow out freely while preventing birds, rodents, and large insects from nesting or getting into the duct system.
Corrugated Flashing / Base (Bottom): The black-colored metallic base features a wavy, corrugated profile designed to match and seal tightly against corrugated metal roofing panels, preventing leaks where the pipe punctures the roof.
These are commonly used in industrial plants, commercial kitchens, workshops, or residential roofs for HVAC exhaust systems or chimney terminations.