Assess enclosure and heat together
A roof with open sides behaves differently from a pavilion with blinds or glass closed around the cooking zone.
Build Project BriefOutdoor Kitchens & Entertaining · Ventilation answer
Some open outdoor kitchens can rely on natural ventilation; more enclosed or higher-output arrangements may need dedicated extraction. The answer should come from the exact appliance and enclosure design.

A roof with open sides behaves differently from a pavilion with blinds or glass closed around the cooking zone.
If extraction is required, hood size, airflow, discharge and makeup air should be designed for the final appliance arrangement and local requirements.
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