We have some spare wood fibre insulation left over from our house build. It’s just the boards in the back of this picture. I’ve checked with the manufacturer and got the advice below on whether it is compostable. Could be used for animal bedding or on an allotment? If you’d like it, pick up on Sunday 19th Jan would be ideal. We estimate it is about a carload.
All of our wood fibre boards are classed as biobegradable rather than compostable. This means that they will break down over time but likely over a longer time-frame than compostable material. Can also confirm that the materials have no additives that are classes as hazardous to the environment. Their official waste code is 030105/170201 which is the same as uncontaminated wood waste. I wouldn’t have any concerns if they were disposed of in the ways you mention below but would just highlight that the rate that the material would degrade would be longer than for truly compostable materials.