1.   An open window will help, but best is an exhaust fan venting air to the outdoors, not into the attic or anywhere else in the house.

2.   As the airship climbs higher and the atmosphere grows thinner, air is vented from the ballonet to keep the pressure within the bladder from growing too great.

3.   The air is then vented up along the outside of the building to a point at least two feet higher than the highest window.

4.   Ventilation is possible, and for all intents and purposes this humid air should be vented outdoors.