I'm somewhat at a loss for words on this, because I haven't yet divined why Gagg would require a griddle plate for updraft ventilation but not for downdraft. Maybe I"m mis-reading griddle plate and what they want is to limit rising heat to avoid overheating _their_ pop-up overhead device. A normal hood at 30+ inches above the burners should not have a heat problem. I wouldn't use a naked back wall with a griddle, though. Tile or stainless steel would provide some safety margin. All that aside, hot cooking effluent rises at a significant velocity. To capture and contain it it with a down draft system is difficult and requires far more air flow than is likely to be present, or even feasible given the aperture sizes in the photos. Turbojet acoustics would follow. The pop up unit gets above the cooking (only one side at a time), but from its apparent size will have poor capture, and then the diversion to down flow via a very small duct will greatly limit the air flow rate. . The NuTone 10-inch fan placed in the wall above the cooking zone performs a kind of side-draft function. I would expect it to be better, but far from ideal. A lot of rising effluent will pass it, unless it is inside of some kind of overhanging hood. Note that without any filtration, the outside wall will be "washed" with greasy smoke and moisture. An overhead hood with mesh or (preferably) baffle grease capture that exhausted through the wall to an exterior fan would be preferable. A modest exterior fan (of the "upblast" style (but not restaurant size) mounted horizontally) would keep the effluent off of the exterior wall. kas

I bet you're a better cook than you're admitting to. These should work on your grill: HERB GRILLED CHICKEN (serves 4) 2-2 1/2 lbs chicken parts 3/4 cup vegetable oil 3/4 cup fresh lemon juice 2 tsp seasoned salt 2 tsp paprika 2 tsp dried basil 2 tsp dried thyme 1/2 tsp garlic powder (or 1 clove garlic, minced) Wash the chicken & put in a heavy zip-lock bag. Combine the remaining ingredients & pour over the chicken. Seal the bag. Marinate in the refrigerator several hours. Broil or grill the chicken 4" from the heat source for 15-20 minutes per side or until done. Baste often w/the marinade.~~Udderly Delicious SALMON WITH GINGER BUTTER (serves 4) 3 TBL dry sherry 2 TBL soy sauce 1 TBL dark Asian sesame oil 1 TBL minced fresh gingerroot 2 TBL minced fresh parsley 2 lbs salmon fillets 2 TBL butter, cut in small pieces 1/8 tsp salt 1/8 tsp pepper 1 lemon, cut in wedges combine the sherry, soy sauce, sesame oil & ginger. Brush the fillets w/the sherry mixture & sprinkle w/parsley. Dot butter evenly across the surface. Season w/salt & pepper. This may be prepared several hours ahead & refrigerated. Broil or grill the salmon without turning until the fish turns pink & flakes easily, approximately 10-15 minutes. Serve w/lemon wedges.~~Gold'n Delicious GRILLED CHICKEN BREASTS (serves 6) 3-4 cloves garlic, crushed 1/2 cup firmly packed light brown sugar 3 TBL whole grain mustard 2 TBL apple cider or dry white wine Juice of 1 lime Juice of 1/2 large lemon 1/2 tsp salt 1/4 cup + 2 TBL olive oil Pepper 6 whole boneless, skinless chicken breasts In a small bowl, combine the garlic, brown sugar, mustard, vinegar or wine, lime & lemon juice & salt. Whisk in the oil & pepper to taste. Place the chicken in a shallow glass dish (or ziplock) & cover w/the marinade. Refrigerate at least 8 hours, turning once. Remove the chicken from the refrigerator & let stand at room temperature 15 minutes. Grill over hot coals or broil 4 minutes per side or until the juices run clear.~~A Taste of New England

I have a 60” dual fuel range, we got a great deal on a floor model, so I wasn’t looking for an indoor grill but it came with the grill and a griddle. I use the griddle all the time... the grill... not so much, and we grill a lot too. It just doesn’t get as hot as my Weber, plus, it’s just not large enough for our needs (we are a family of 7). I use it here and there in the winter, mostly for grilling things like vegetables or pineapple because it does just fine for that. The clean up is a real hassle (though clean up for my griddle couldn’t be easier) and I just hate that part of it, it does keep me from using it sometimes. I do have a great vent and system that takes care of the smoke and odors, but I wanted that anyways because we do a lot of high heat cooking even without the grill. If I could do it again, I’d rather have double the space for the griddle and not have the grill at all. I much prefer my outdoor grill, we use it almost year round even though we live in a cold climate as well... it just doesn’t heat well for me on the coldest and windiest days, so a more sheltered location for my outdoor grill would be higher on my priority list than an indoor grill if we ever have to move again. Hope that helps!

Obviously such grills are intended for outdoor use and I’m not what anyone would call an “expert” but I’m just wondering... The Char-Broil you referenced puts out about 40,000 BTU’s on it’s highest setting. That’s about the same as higher end gas range if one was to use all the burners or some burners and the oven. Certainly there are people who use their stove without the exhaust fan or have an exhaust fan that vents to the inside. Perhaps a range is designed to burn more efficiently as carbon monoxide is the byproduct of incomplete combustion. Would opening in a window (or two) provide enough fresh air to offset any carbon monoxide that was produced? I would definitely be worried about the potential for smoke to stain the ceiling and perhaps walls. Without ventilation odors would probably linger for a while too. Protecting the floor from any grease drippings would also be important. Finally would be clearance from combustibles, read the manual for your grill but I’d guess 3 feet as a minimum. Not to quibble but the common cold and the flu are the result of exposure to a virus, not cold weather.