Utility Rooms and Combustible Air: When you finish your basement typically you enclose the utility area which consists of the furnace, hot water tank, and the boilers. These items burn gas and need as much air possible for a clean burn and in exhausting. Sometimes alternate air sources are needed to prevent negative air or sitting problems. This need for air can be overlooked, and the grill in the door may not be enough for an air supply.  Do not starve your gas appliance or exhaust systems of needed air.