8"-10" Dual Outlet High Performance Roof Cap for BBQ Hoods

The 8-10" BBQ Dual Duct High Performance Roof Cap terminates two separate duct runs through a single roof penetration. Each outlet accepts either 8" or 10" rigid duct, and the two paths stay independent all the way through the cap — no Y fittings, no merging, no shared discharge opening.

Two ducts in, two ducts out

Proline BBQ Wall Canopy and BBQ Island hoods vent through two 8" ducts rather than one. The common workaround is a Y fitting that merges both runs into a single larger duct before the roof. That transition is where airflow gets lost: combining two streams into one creates turbulence, raises static pressure, and makes the blower work harder to move less air.

This cap eliminates that step. Each run keeps its own path from the hood to open air, so the exhaust volume your hood is rated for is the volume that actually leaves the building.

Features

• Two independent duct outlets — each run vents on its own. No Y fittings, no merged airflow, no shared discharge.
• Accepts 8" or 10" rigid duct — each collar fits either size, so one cap covers the dual 8" runs on Proline BBQ hoods and larger 10" systems alike.
• Single roof penetration — both runs exit through one flashed opening instead of cutting and sealing two.
• High-CFM airflow path — engineered for the discharge volume of Proline's outdoor BBQ hoods, not scaled down from an indoor cap.
• Weather-resistant construction — PAC-CLAD powder coat steel is built to hold up to sun, rain, snow, and freeze-thaw cycles.
• Integrated flashing — square perimeter flange for a clean, watertight penetration.
• Backdraft protection — inline dampers included on each outlet keeps cold air, wind, and pests from traveling back down the duct.
• Bird and debris screen — mesh screen blocks nesting without meaningful restriction.

What it fits

• Proline BBQ Wall Canopy (BBQ WC) outdoor range hoods — dual 8" duct configuration
• Proline BBQ Island outdoor range hoods — dual 8" duct configuration
• Any two-duct exhaust system using 8" or 10" rigid duct

Installation notes

Run both ducts to the cap as separate lines. Do not combine them with a Y fitting or reduce duct size anywhere between the hood and the roof — either move undoes the benefit of a dual duct system.

Keep runs as short and straight as possible, use rigid duct rather than flex, and seal all joints with foil tape or duct sealant. Follow local building codes for clearance from ridges, valleys, and adjacent openings.

Specifications

Frequently asked questions

Does this combine both ducts into one outlet?

No. The two duct paths stay completely separate through the single cap and discharge independently. Nothing is merged or transitioned into a single larger duct.

Can I run 8" duct to one outlet and 10" to the other?

Each collar accepts either size, so mixed configurations are possible. That said, matching both runs to your hood's outlet size is the better setup — mismatched duct sizes create uneven resistance between the two paths.

My hood has dual 8" outlets. Do I need to upsize to 10"?

Not necessarily. Run 8" the whole way if your duct length is reasonable. Upsizing to 10" can help on long runs or installations with multiple elbows, where cumulative resistance becomes a factor.

Can I use a standard single-duct roof cap instead?

Only by Y-ing both runs into one, which is exactly the restriction this cap is built to avoid. Merging two streams into a single opening raises static pressure and cuts effective CFM at the cooking surface.

Will this work for a wall-mounted duct run?

This cap is designed for roof terminations. For a horizontal run exiting through a wall, you'll want a dual duct wall cap instead.