The room or space containing the Pyroclassic needs no additional ventilation unless a draught stabilizer is fitted, in which case a permanent opening of at least 1500mm2 should be provided. Any air opening must be kept clear from blockage and obstruction. Due consideration should be given to air requirements for any other appliances in the same room or home, such as heat transfer kits, kitchen range hoods, laundry dryers, bathroom vents etc.
If your fire has been installed into a new build home, these are constructed to be far more air tight than older housing can have an significant impact on the free air available over time to the fire, especially when other forms of mechanical extraction from within the home are used such as range hoods, dryers, wet room extraction etc. In severe cases the flue pipe can actually end up being used as the means of ventilation causing the flue gases to then be drawn into the house. This is not a fault of the fire but a flaw in the inadequate ventilation planning of the house construction and NZ building code.
A further point of note on the house topic is the location of the house in relation to its surroundings and the termination of the flue system, this is often referred to as downdraft.