Adding Vent to Laundry Standpipe

[qlopp]

Hi,

I have a restricted trap below my laundry standpipe that can no longer handle the spin cycle output of my washing machine. It is the original installation from 1962; a 2" cast iron pipe goes below the concrete floor to a buried trap. Several times over the last 15 years I was able to snake it out with a 3/8" power drum snake and small "cutter" (I took a beehive attachment and cut off all but a little spur of the wire so that it would be slinky enough to make it through the trap). I can't snake it anymore due to corrosion bloom inside the trap.

This standpipe is just a stub and is not vented externally. It is located in a corner of the basement, 9" from the gable end wall of the house and 36" from the front wall of the house. It is one foot horizontally from a hopper window on the gable wall.

I've done research on what the correct repair would involve, which is to bring it up to code by cutting out the old trap and retrofitting an above floor trap. Then the drain must be vented to the exterior. It is here where I am unsure about all of the plumbing code stipulations. Paraphrasing from several sources, the vent terminal must be 10+ feet above outdoor ground level, then it must be 10+ feet horizontally from an openable window/door or intake/exhaust port unless it is 3+ feet above such opening(s). Unfortunately there is a basement hopper window very close to the drain location and one window each on the first and second floors above that window. By the time I navigated around these restrictions I would be at the attic level. Therefore roof exit seems like the only choice.

I am in an unincorporated county area which has adapted IPC. We have the least layers of government oversight in the populated areas of the greater metro area. Is there any chance of being granted a variance for retrofitting such a code compliance upgrade in a simpler manner than going all the way through the roof? Maybe a wall exit compromise that inspectors would allow in this situation, given the difficulty of achieving full compliance? It's not a conventional soil stack (so no human or food waste) and the trap breaks vapors from the lateral it connects to, so I don't consider that unreasonable.

If I hire a company to do this, how involved is running a pipe inside the exterior wall, up two stories and through the roof of a stick frame house, including flashing/roofing restoration and patching/restoring the appearance of any access holes in the walls? It seems like an expensive proposition, but maybe it's not as bad as I'm thinking.

Thanks for reading!

 

[Reach4]

How about a photo that includes the trap and related stuff.

IPC. https://ecode360.com/27703412
AAVs are allowed.

 

[Sponsor]

 

[qlopp]

How about a photo that includes the trap and related stuff.

IPC. https://ecode360.com/27703412
AAVs are allowed.

I'll get to taking pics ASAP, maybe tonight.

 

[qlopp]

How about a photo that includes the trap and related stuff.

IPC. https://ecode360.com/27703412
AAVs are allowed.

Sorry it took so long. The PVC standpipe you see is a temporary measure I took to try to get better leverage on the power snake before giving up on cleaning out the subgrade trap. I figured that the floor was going to get busted up soon enough anyway to make a permanent fix so I cut the original cast pipe near the floor, hoping that the closer distance and less snake whip would allow me to get it through the trap.

That small diameter copper pipe is from the HVAC condensate pump. There is no floor drain in the room with the HVAC unit.

The drawing shows my plan. Before researching venting regulations I had hoped to make a 90 degree elbow turn through the basement wall then terminate the cap/hood right there, but as mentioned in my original post the window and ground height restrictions make that impossible. I would rather spend a large amount of money having a pro do it right so as to avoid the eyesore of plumbing it outside, then extending the pipe externally above roof level. While that is something I could do myself for cheap it would look awful.

I figure that if I upgrade this following my plan (see drawing), at any time in the future that it's deemed necessary to vent it externally to code, my vent pipe could always be joined by a professional to a pipe that he would run inside the walls of stories 1 and 2, then exit through the roof.

Going forward with that plan, I can place my new above grade pipe anywhere between where I decide to cut the subgrade cast iron arm and the exterior wall. Right now the standpipe is 9" on center from the wall. Is there any benefit to having it closer or farther away? I was thinking that a little closer might be less cumbersome but that air space it will take up isn't really being used by anything. I haven't seen any recommendations or code regulations for pipe stack distance from a wall.

Finally, I was thinking of angling the standpipe/trap portion towards the wall to take up less horizontal space and make bracing to the wall easier. Could it be practically touching the wall without violating any regulations?

 

[John Gayewski]

Your drawing looks legal and the trap can swing toward the wall. All good.

 

[qlopp]

Hi,

I have a restricted trap below my laundry standpipe that can no longer handle the spin cycle output of my washing machine. It is the original installation from 1962; a 2" cast iron pipe goes below the concrete floor to a buried trap. Several times over the last 15 years I was able to snake it out with a 3/8" power drum snake and small "cutter" (I took a beehive attachment and cut off all but a little spur of the wire so that it would be slinky enough to make it through the trap). I can't snake it anymore due to corrosion bloom inside the trap.

This standpipe is just a stub and is not vented externally. It is located in a corner of the basement, 9" from the gable end wall of the house and 36" from the front wall of the house. It is one foot horizontally from a hopper window on the gable wall.

I've done research on what the correct repair would involve, which is to bring it up to code by cutting out the old trap and retrofitting an above floor trap. Then the drain must be vented to the exterior. It is here where I am unsure about all of the plumbing code stipulations. Paraphrasing from several sources, the vent terminal must be 10+ feet above outdoor ground level, then it must be 10+ feet horizontally from an openable window/door or intake/exhaust port unless it is 3+ feet above such opening(s). Unfortunately there is a basement hopper window very close to the drain location and one window each on the first and second floors above that window. By the time I navigated around these restrictions I would be at the attic level. Therefore roof exit seems like the only choice.

I am in an unincorporated county area which has adapted IPC. We have the least layers of government oversight in the populated areas of the greater metro area. Is there any chance of being granted a variance for retrofitting such a code compliance upgrade in a simpler manner than going all the way through the roof? Maybe a wall exit compromise that inspectors would allow in this situation, given the difficulty of achieving full compliance? It's not a conventional soil stack (so no human or food waste) and the trap breaks vapors from the lateral it connects to, so I don't consider that unreasonable.

If I hire a company to do this, how involved is running a pipe inside the exterior wall, up two stories and through the roof of a stick frame house, including flashing/roofing restoration and patching/restoring the appearance of any access holes in the walls? It seems like an expensive proposition, but maybe it's not as bad as I'm thinking.

Thanks for reading!

Update, I had finished the main repair work on this standpipe weeks ago but just got around to making brackets for the pipes to complete it.

Turns out the trap wasn't blocked so much as it was rotted out at the bottom such that my snake got stuck in the rotted out section rather than turning and making its way toward the arm. The dirt aka mud was nasty from that leakage. The pipe still needed to be cleaned after

Bonus, at the same time I lucked into a free circa 2005 washing machine to replace my worn out one which was not cost effective to fix anymore. I disassembled/cleaned up the "new" Kenmore and found out it works perfectly.