Horizontal Pipe Discharge Through Roof

For example â measure a distance x of 24 inches across the top of the flowing discharge from the end of a 2 inch diameter pipe.

Horizontal pipe discharge through roof. May be measured at horizontal distances x from the pipe exit of 6 12 or 18 inches. All open vent pipes that extend through a roof shall be terminated at least number typically 6 inches mm above the roof except that where a roof is to be used for any purpose other than weather protection the vent extensions shall be run at least 7 feet 2134 mm above the roof. If it slopes downward the indicated discharge will be too low. 2 56 times 24 times 2 squared divided by the square root.

Window or fresh air intake. If it slopes upward the indicated discharge will be too high. New york state just raised plumbing vent pipe code from 12 inches to 18 inches above the roof and at least 10 feet horizontal distance from any opening to the building i e. Then by the formula the flow in the pipe in gallons per minute is.

1 place the ruler on top of the discharge pipe and extend it out far enough out so that the plumb bob or ruler spans the length of the jet flow portion of discharge see figure xxx 2 slide the ruler back along the pipe as needed to measure the jet flow segment of discharge. Then measure vertically to the top of the liquid discharge y say it is 25 inches. In modern roof drainage design a horizontal gravity pipe could be sloped to take up to two thirds water with a one third air mix depending on gradient.