People die every winter from having improperly vented gas combustion appliances in their home. If you want to grill in doors, it requires a POWERFUL ventilation hood, and heated Make Up Air.

Thank you for warnings, you are right. I have not such a good ventilation system for this purpose. But what about using electrical grills? I found some here, they look safe. Of course, nothing can replace charcoal grill, but burning down the house or suffocating with CO is not a solution. Do you have experience with this type of grills? I've never taken them seriously, but I can get ill because of somebody sneezes once near me, so it's not a good idea to use my Char-Broil outdoors in winter.

A small Zojirushi indoor electric grill can get you grill marks and some caramelization. So can a cast iron stove top grill pan. It’s not a substitute for fire. Outdoor grilling is done 365 for those who are motivated enough to make it happen. Plenty of Packer fans don’t seem to be too affected by -40.

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.

I live in CO, where we can have below zero weather in the winter, and we grill outside all year round. I also have a range with a built in grill that is unusable because it always sets off the smoke alarm. It's also a pain to clean, so I never use it and will never buy a range with a grill again. I suggest that if you have the right setup for it (such as a deck off your kitchen), you invest in a good outdoor grill. Our Big Green Egg is wonderful for winter grilling--the ceramic holds in heat well and makes the cold weather almost a non-issue. :-)