Any wood burning sauna heater requires a chimney or flue. With all Narvi, Aito and Kota wood burning sauna heaters, a T600 rated or greater flue kit should be used. The simplest and most cost effective solution for a wood burning sauna heater flue is a Flue Kit. These come with all the parts required for either single or two-storey buildings. Also in this section are stone cages, water tanks and heat shielding designed for sauna flues.