How big must a building/spaceship be to create an indoor weather system?

The NASA Vehicle Assembly Building and the proposed Nazi Volkshalle are cited to be "big enough for weather systems to form inside them".

The building has at least 10,000 tons of air conditioning equipment, including 125 ventilators on the roof supported by four large air handlers (four cylindrical structures west of the building) to keep moisture under control. Air in the building can be completely replaced every hour. The interior volume of the building is so vast that it has its own weather, including "rain clouds form[ing] below the ceiling on very humid days",[8] which the moisture reduction systems are designed to minimize.

The same problem would undoubtedly occur to spaceships, which would also suffer from the problem of interior cloud formation.

How large can an indoor chamber (i.e. a bubble habitat, spaceship) become before it will start to rain indoors due to condensation? Assume 50% RH in the air at ground level, for the purposes of this question, as such habitats are almost certainly going to be humidity controlled.

posted over 9 years ago

March Ho‭

11 reputation 2 1 1 0