the period of time, the sidereal day, during which the earth makes one complete revolution on its axis relative to a particular star. The mean sidereal day lasts 23 hours 56 minutes 4.1 seconds of the mean solar day.
In this corner: a vent stack is series of vertical pipe vents that passes through at least two stories and is meant to maintain atmospheric pressure in the drainage system. The vent stack usually runs parallel with the soil/waste stack and may either extend up through the roof or connect to a stack vent. And in this corner: a stack vent is the uppermost portion of a soil/waste stack that continues the pipe from above the highest connected fixture out the roof.
All Pop Vent Roof Louver Models by Diameter and Collar Size. Note: 1 Collar vent models for Pitched Roof applications. Excellent on Steep Slope Roof Applications. Active Ventilation Products' Pop Vent also known as the Roof Louver is an excellent roof vent for ventilating attic spaces on steep slope roof applications. The Roof Louver will add necessary roof top ventilation to alleviate moisture from the attic in the winter and heat in the summer.