I think the term "building" is a bit of a stretch. Mostly the geodesic domes seem to be used as small greenhouses, and don't have enough weight that even a sudden collapse would really damage the occupants. The manual suggest that the maximum weight for the whole structure should be about 60kg. I'm not really concerned that these things aren't meeting fire code either, you know? You can just pick a wall and tear through it in almost all the examples I've seen in the gallery.

That being said the glass transition point of ABS plastic is 105'c, a little over boiling. I'm not worried about ABS from a thermoplastic perspective, although I am worried about long-term UV performance. I'd also be worried about thermal cycles and plants/mold as most 3D printed ABS will take on water.

I think you'd get a few years out of an ABS plastic component in these circumstances, more if you resin coat it or use acetone vapor smoothing, and start with a filament that has good UV resistance.

Either way I expect 3D printed components to be more expensive and otherwise worse than one manufactured by this company, but being able to repair stuff like this if you need to is important and it's not like you can just go to the hardware store and get a replacement one of these hubs.