Dear helpful plumbers, the following are my problems: the basement bathroom sink is connected to a main floor kitchen drain line (about 15-20 ft away) which subsequently flows to the drain on a toilet 3 ft away which then flows to a shower another 3 ft away and then, finally, to the main drain. There is no air vent in this line except back at the kitchen sink. The toilet bubbles vigorously and will splash when the kitchen sink is drained with the garbage disposal on. The closest vent is a near central laundry room vent on the main floor about 10-15 feet from the basement sink - toilet- shower combo. How can i vent the basement bathroom to prevent all the toilet blowback? The toilet and shower seem to plug up very easily too...often food from disposal will end up in the shower. I want to reno this bathroom but not before the plumbing problem is solved. Is the best solution to smash the concrete and plumb vents into all three fixtures, tie them together and send this to the roof?

yes - individual fixture venting is best practice

however

may not be required either by code or functionality

there are MANY things which could have the effect you are describing:

pitch issues

partial stoppage

sizing

improper use of fittings



an 'on site' inspection by a COMPETANT plumber is indicated

look for one who is licensed, insured, AND BONDED (if possible)

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



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I think you have issues other than just venting. The kitchen sink drainage should push the air past the toilet and up through other vents in the system rather than up through the toilet.
As has been said, it will likely take a visually inspection to properly diagnose the faults.

If you get food waste coming back up through the shower and the shower is the last fixture before the main, there is a restriction in the drainage piping in the main or between the shower and the main. This restriction needs to be mechanically cleaned with proper equipment(no chemicals) or repaired. If the drains previously ran good, with no air burping/shower back flowing, I wouldn't worry about the venting.

I understand except that there are no other vents to push the air to i.e. there is not even one vent for the basement sink/toilet/shower combo. I will have a thorough inspection/recommendation made by a qualified plumber. Thanks.

I think that the toilet has been burping badly since we moved into the house 12 yrs ago...but this could be because there is no vent at all and perhaps build up between the shower and the main. Getting access to the sink pipe to install a vent is possible with some drywall removal but the toilet and shower would require smashing open the cement floor (just a guess). I will have a visual performed by a competent plumber and thanks for the input.



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quote..."yes - individual fixture venting is best practice"
SO, if you have back to back bathrooms..
bath 1 has a toilet, a tub and a lav.
bath 2 has a toilet, a tub, a shower and two lavs.
following your 'best practice' thinking, you would install 8 individual vents?
a schematic of your work would look just like an octopus.

Steve is correct about the partial blockage. If you have been having problems for 12 years, I would worry that there is a structural issue causing the problem. Get the line professionally cleaned with an auger, and have the line video inspected for obstructions, damage, or any other structural issues.

packy,

the 'cross sanitary tee' used for the back to back lav = 1 vent serving 2 fixtures

etc.






for multiple story bldg. add a separate vent stack

hj, perhaps you could explain with better pics ?




==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

Thanks for the images...it helps clarify the possibilities. Once i have the pipes mapped out and a recommendation for a "fix", i will report back the conclusions.

Thanks again.