

From the top since you seem to have forgot;
This is a really cool project and really speaks to the changing nature of warfare. And, once again, highlights the real reason so much money has gone into FDM processes.
If warfare is not “the real reason so much money has gone into fdm” why did you say it was?

Those are super neat. I saw a video about how that was sidelined when they made the insulation regulations in the 1900s, which was a real bummer.
One of the things to consider, beyond the dry climate requirements mentioned already, is that you can’t use it as a drop in replacement for fiberglass insulation. You have to plan the building around it because it requires a lot more space, relatively speaking.
*edit In the USA. Can’t speak for australia, which is what you linked to.