In principle, Pio8 Ventilator is installed at the ridge of a building. It creates a region of lower temperature and thereby lower pressure, so that hot air from within the attic (space between roof and ceiling) is drawn up to the lower temperature region (heat flows from hot medium to cold medium) and exhausted into atmosphere through the Pio8 ventilator outlets (Hot air rises). Once the hot air is drawn out from the attic, it creates a negative pressure (vacuum) within that area.As the result, air is drawn out from inside of the building (interior) through the ceiling vent holes. Fresh and cool air will move in from widow and door to replace the valume of air draw out to the attic. Indirectly, it will form a convection loop. As long as the temperature different between inside and out side, air exchange take place. Moreover, the Pio8 ventilator outlets being located the top of the unit takes advantages of the principle that hot air rises and minimizes any adverse effec on air exhaustion by atmospheric wind and also out of sight from ground level.