We have a built in grill under cover, no hood and have no issues. An angled steel plate secured to the fir beam above the grill and an 18 inch opening above that funnels the grill smoke out and away and protects the beam from heat. You can see the plate in the picture below if you look closely. In the house pic the grill is located on the left side of the deck behind the solid wall.
edited to add-the items directly above the grill on the ledge do get greasy, the tv area to the right behind the open door and the bar area to the left do not.
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LaCantina Doors
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