* The air ventilation does not work with the own convective pressure in this prototype. This again can be due to the slim shape. Therefore, an additional gentle push is required. Placing the air outlet on an appropriate location of the roof is good enough, letting the wind pressure do the work.
* If thuja or other biomass with strong aromatic oils is put in, the microbial activity is impeded and the temperature declines. This effect is subject to further studies. It may be useful for pausing the decay process during the warm summer months.