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Washing Machine vent pipe

What is the vertical rise? Don't have my books in front of me, bt if memory serves, that is a factor............
 
Skip,

"Washing machine drain is 2" with a 1-1/2" vent that travels 60'. Is the vent sized correctly? "

Yes, see 2006/2009 IRC, Section P3113 Vent Pipe Sizing.

P3113.1 Size of vents. " The minimum required diameter of individual vents, branch vents, circuit vents, vent stacks and stack vents shall be at least one-half the required diameter of the drain served. Vent pipes shall not be less than 1 1/4 inches in diameter. Vents exceeding 40 feet in developed length shall be increased by on nominal pipe size for the entire developed length of the vent pipe."

2" drain = 1" vent; except that the least vent size allowed is 1 1/4". Over 40 feet developed length = one "nominal pipe size" increase. So actually 1 1/4" would meet the code requirements.

Interesting note about not allowing less than 1 1/4" vent pipe. Your not going to believe it, but, 1" vents whistle. :)

Hope this helps,

Uncle Bob
 
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