I have an inspector requiring a CO detector at receptacle height on the inside of a house, next to the door leading to the garage. This is a remodel. Originally we had a combo smoke/CO detector in the hallway and that was fine. The owner got a second permit to construct a bathroom and bedroom in a portion of the garage. Now he wants a CO detector as I described earlier. My question is, have you done this before and did it tie into the smoke alarms or was it a stand alone unit. I know I can go online and find these products, but I'm curious as to where this requirement for a dedicated CO detector might have come from. This was told to me by the HO, as per the inspector.