Quotes from the book Bucky Works, by J. Baldwin, p 123, chapter Leaks
A new technology may have an entirely new type of problem that takes engineers and trades worker by surprise. The tendency of geodesic domes to leak is an example of such a problem. .. the geodesic pattern distributes stress - the forces acting on the structure - evenly and almost instantly throughout the entire dome. That's what gives geodesic domes their remarkable strength per pound of material. ... When the sun heats one side of a dome, the warmed materials expand ... A dome consisting of separate panels may open gaps between the panels. In other locations, it may tighten the gaps, squeezing out seals or caulk. In a dome with a one-piece skin - welded metal or fiberglass, for instance - the dome distribute the strain by distorting.
Today's commercial designs not only don't leak, they can't leak. Their permanent, precision parts are mass-produced in automated factories, giving a very high standard of fit and finish not vulnerable to careless assembly at the building site. Clever, long lasting silicone seals keep working without fatigue. Some designs don't even require seals.