It takes approximately two minutes to fully inflate a Chimney Balloon. You’ll find that you can breathe normally while your chimney is being cleared too! Keep in mind, this time may vary depending on how much use there has been of the fireplace before using the Chimney Balloon. If it’s been a long time since the fireplace has been used, you can expect to have about five minutes added onto that two-minute period because of how much soot and grime is built up in your chimney.