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06f150
Jun 29, 2009, 07:41 PM
Went a took a look at a bathroom today and I have a question.

About two months ago A "handyman" came and replaced the leaking kitchen sink drain pipe above that also is a wet vent to the bath sink and toilet directly below it. From what I could tell it was originally 2" and he used 1" 1/2 for his so called "repair" (it goes back to 2" about 12" before it goes into the slab). He also completely disconnected the bath sink from the drain... why?. ummmm...

What I want to know before I turn in my estimate does that pipe need to be replace again back to the original 2" that was there??...I would think yes.

To recap the kitchen sink/dishwasher above uses this 1 1/2 as it's soil drain, and the toilet below, and the bath sink (or did when it was hook up to the 2") uses this as a wet vent.


Thanks

Edit: A toilet is a min. of a 2" vent correct?

massplumber2008
Jun 30, 2009, 05:07 AM
Hmmm...

A kitchen sink or a washing machine drain CANNOT be used to wet vent any fixtures, so that sink must have been added at a later date than the other fixtures... yes..?

The correct thing to do here would be to run a separate 2" drain from below the bathroom fixtures and run that upstairs to pick up the kitchen sink. Then , have the plumber increase the 1.5" pipe back to 2" pipe so the bathroom fixtures below are vented properly (2" is fine for a complete bathroom setup). The 1.5" kitchen sink vent (new) will then connect into the 2" vent at approximately 42-48" off the finish floor.

Otherwise, at a minimum increase that drain back to 2"... although with sink waste running past the toilet and sink drains you are getting sewer gasses into the home so I think that is the bigger issue.

Let me know if you want to discuss this more...

MARK

PS: A toilet requires a minimum 2" vent.

06f150
Jun 30, 2009, 06:39 AM
Hmmm...

A kitchen sink or a washing machine drain CANNOT be used to wet vent any fixtures, so that sink must have been added at a later date than the other fixtures...yes...??

The correct thing to do here would be to run a separate 2" drain from below the bathroom fixtures and run that upstairs to pick up the kitchen sink. Then , have the plumber increase the 1.5" pipe back to 2" pipe so the bathroom fixtures below are vented properly (2" is fine for a complete bathroom setup). The 1.5" kitchen sink vent (new) will then connect into the 2" vent at approximately 42-48" off the finish floor.

Otherwise, at a minimum increase that drain back to 2"....although with sink waste running past the toilet and sink drains you are getting sewer gasses into the home so I think that is the bigger issue.

Let me know if you want to discuss this more...

MARK


PS: A toilet requires a minimum 2" vent.

Umm, I don't think the kitchen sink was added later. House was probably built in the 70's. (trust me, nothing has been done to it as it still has orange/green carpet!).

One thing I forgot to add was that there was also an shower in the lower bath that used this same 1.5"(again was a 2") as it's wet vent, but it has been disconnected for some time.


So If I am understanding this right. A new 2" vent is needed for the bath fixtures below, and then pick up the 2"sink vent above the sink 48"?? Or does it need to vent straight outside (this new 2" vent)?


Then return the 1.5 back to 2" for the kitchen sink.


Thanks

massplumber2008
Jun 30, 2009, 08:57 AM
Either put it back as it was... 2" all the way....OR, use the kitchen sink drain (the pipe reduced to 1.5" acting as a wet vent for everything) as the vent for the downstairs bathroom (increasing back to 2") and then run a new 2" pipe up from the basement waste pipe to the kitchen sink. At the kitchen sink you will reduce the kitchen sink vent to 1.5" and then connect it into the existing 2" vent from the bathroom below.

Here, you are just removing the kitchen sink drain off the piping in place now which should leave it as a vented line going up and out the roof (or connecting to other vents upstairs) and then running a new 1.5" vent (connecting into 2" vent at 42-48" off finish floor into the existing vent) and 2" waste for the kitchen sink up from below the other plumbing downstairs.

Since your plumbing has been in place since the 70s... I would probably just increase the pipe size back to normal and be done with it. I just wanted you to know your options... ;)

Hope that helped...

MARK

06f150
Jun 30, 2009, 09:41 AM
Either put it back as it was....2" all the way....OR, use the kitchen sink drain (the pipe reduced to 1.5" acting as a wet vent for everything) as the vent for the downstairs bathroom (increasing back to 2") and then run a new 2" pipe up from the basement waste pipe to the kitchen sink. At the kitchen sink you will reduce the kitchen sink vent to 1.5" and then connect it into the existing 2" vent from the bathroom below.

Here, you are just removing the kitchen sink drain off the piping in place now which should leave it as a vented line going up and out the roof (or connecting to other vents upstairs) and then running a new 1.5" vent (connecting into 2" vent at 42-48" off finish floor into the existing vent) and 2" waste for the kitchen sink up from below the other plumbing downstairs.

Since your plumbing has been in place since the 70s...I would probably just increase the pipe size back to normal and be done with it. I just wanted you to know your options...;)

Hope that helped...

MARK

Ah.. I get it now.

I also just took another look at the job and I guess the house was built in 1958. The lower bath was added latter, hence why it is not right.

Also, the wet venting pipe is 1.5" all the way to the roof line,the only 2" part of it is about 12" above the slab as I said before (which is part of the repair).

So if I were to have done what you said above the toilet is still below code as it is only 1.5" vent... correct?


By the way, found an old and empty bottom of whiskey up in the ceiling... maybe this explains why the plumbing is all jacked up>lol
Thanks again

massplumber2008
Jun 30, 2009, 10:59 AM
Correct... but as some old time plumbers say... an 1.5" vent is better than no vent at all... ;)


MARK

06f150
Jun 30, 2009, 03:50 PM
Correct...but as some old time plumbers say...an 1.5" vent is better than no vent at all...;)


MARK


True...

Just got off the phone with my plumber and the home owner and she does not want to pay any extra to make it right. I kindly told her it is this way or no way. She then suggested completely taking the bath out, capping all lines and turning it into an storage area/ small work area.

I guess that would work too.

massplumber2008
Jun 30, 2009, 04:01 PM
I guess so... LOL

Nice that you took the time to investigate this for her...

Pop back anytime if you think we can help again!

06f150
Jun 30, 2009, 04:05 PM
I guess so...LOL

Nice that you took the time to investigate this for her...

Pop back anytime if you think we can help again!



You bet!


Thanks for the help.



Josh