I am finishing my basement of my condo, adding a bathroom and
bedroom. I plan to build a small room around the furnace and the
water heater. What do I need to do to ensure that the burner of the
furnace gets a good supply of fresh air? Since people will be
spending a lot of time in the basement, do I need to run an air supply
line to the outside of the house to prevent a buildup of CO2 or CO?