A radiative cooling structural material

Being made entirely out of sugar, there must be something that can eat it, and will -- presuming indigestible lignin is in the way, in regular wood.

It doesn't say anything about water resistance or absorption.

Oops, it does. They suggest hydrophobic surface treatment. It is interesting that it would naturally accumulate condensation in ambient light.

Earlier submission, still on front page:

Interesting stuff. As for cooling, it wont take long to get even slightly dirty, negating all the cooling effects.