When installing your vents it s highly recommended that you plan out your drain lines to minimize the risk of clogging.
Examples of 2 inch waste vent at roof.
Section 904 vent terminals roof used as.
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.
Above roof plumbing vent diameter.
The diameter of individual vents branch vents circuit vents and relief vents shall be not less than one half the required diameter of the drain served.
Located on the roof these vent pipes allow gases to escape from your sewer system.
Because the vent pipe is the warmest pipe in the house all year long the moisture that is trapped in a bend may turn to vapor and cause a vapor lock.
The fat pipes in your house make up the dwv carrying wastewater to a city sewer line or your private sewer treatment facility called a septic tank and field.
Plumbing vents need to be straight on the vertical.
A secondary stack perhaps 2 or 3 inches in diameter serves a branch of the system.
Here s a closer look at this issue.
The centerpiece of a dwv system is the main stack usually a pipe 3 or 4 inches in diameter that runs straight up through the roof.
When there is a bend in the vent pipe moisture accumulates and is trapped.
All open vent pipes that extend through a roof shall be terminated at least number 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.
This is necessary to avoid any vapor locks from occurring.
Both kitchen 1 1 2 inches and bathroom 1 1 4 inches are smaller than the rest of the drain system on purpose.
The required size of the drain shall be determined in accordance with table 710 1 2 vent pipes shall not be less than 1 1 4 inches 32 mm in diameter.
Concluding the example we will assume the restroom has its own vent to the roof with a total piping length of 25.
They lead into larger branch drain pipes which lead into the 4 inch stack.
904 1 roof extension.
Signs that your sewer vents are blocked.
Consulting ipc table 916 1 see figure 4 we see that for a 4 waste stack with a dfu up to 140 and with 27 or less of vent piping length the correct vent pipe size is 2.
If they become blocked your system won t drain properly.
Branch drainpipes of smaller diameter typically 1 1 2 or 2 inches carry water from specific fixtures to a stack.
Vents exceeding 40 feet 12 192 mm in developed length shall be increased by one.