We are trying to recycle any products we can. These slats, originally from our lathe and plaster walls in our house have been trimmed and de-nailed to fit between the joists. The membrane (leftover from outside wall) has been laid over the lathes and then we covered it in hempcrete, same recipe as ceiling insulation (no sand and half the lime). This will provide the most amazing floor insulation.
We are a little nervous as our dog is not terribly bright and is likely to walk on the setting hempcrete insulation.