Roy Starrin wrote:

wrote:

I bought a home that has an addition which is built on concrete
pillars, much like a deck would be. The builder put fiberglass
insulation between the floor joists, and it just fell out onto the
ground (brilliant, eh?).

As discussed, chicken wire will work...

So would foil, for downward heatflow, eg thin double-foil foamboard
with no other insulation.

Nick