Cleanouts for Horizontial Vent Section?

[chuyser]

What type of cleanouts and where can they be located for the following situation?

I'm converting a second floor shower to a whirlpool bath. The main 3" vent rises from a cross positioned just below the second floor joists in a soffit in the first floor ceiling. Unfortunately, the vent rises up through the only space where the whirlpool can be positioned. For a combination of reasons, 45 degree elbows do not provide enough offset to allow the stack to pass outside the tub space.

As an alternative, can I turn the stack horizontial just above the cross with a 90 degree elbow, run horizonal a few feet until the stack is outside the tub space, then turn the stack vertical again with another 90 degree elbow?

It is my understanding that eventhough none of these rerouted vent pipes will carry water, they must have a cleanout. Is this correct?

If so, does the cleanout need to be at the end of the horizontial section? Or can the cleanout be angled up 45 degrees so that it is accessable from above the floor?

Or can the clenout be in the vertical section several feet above the 2nd floor? If so how far up is acceptable?

Finally, can the vent be reduced "one size" to 2" so that the radius of the elbow turns is smaller?

[hj]

Where the cleanouts should be placed would be determined by the piping you have not described. In most cases it would be in the vertical pipe in the lower level, just before it went into the floor assuming there is no basement, if here were it would be in the basement pipe.

[chuyser]

Perhaps a picture will clarify my question. On the 2nd floor, the stack vent rises through the space where I'd like to install a whirlpool tub.

Can I offset the stack vent about 3 feet with 90 degree elbows? This is shown in red in the diagram. (While I think I understand that 45 degree elbows would not raise the cleanout issue, they just don't provide the lateral displacement that I need.

If so do I need cleanouts at either end of the horizontal runs?

Of course the revent would have to tie in to the relocated stack vent, just as it did in its old location.

Thanks in advance for any insight to this problem.

[master plumber mark]

from your drawing you really dont need
cleanouts above that mess youi ar going to install.

nothing but air travels through it anyway.

now if a bird or some unlucky squirrell falls down that stack
tou will jsut have to worry abouit that when or if it would
ever happen....

for that matter , just install a chcken wire
mesh screen over the stack out the roof if it
makes you sleep better.


like MR HI said earlier, all ya got to have is a way
to clean out the system from the basement where it counts...


air is air and doesent know you are makeing lots
bends to the pipeing.

good luck

[finnegan]

I try to put a cleanout in the attic before the stack penetrates the roof so you can get a snake from the top down without going on the roof. Though, this is not required.

[master plumber mark]

go ahead if you must...

if it is somehow going to make you sleep better, then do it....

all you are going to accomplish is probably loosen or crack the
flashing at its seal going out the roof and make it leak during the next good
downpour.....

but you got to do, what you got to do.

[Cal]

There is nothing REALLY wrong with what you want to do.However it would help if you could get some pitch on that vent. Have you thought about 2 60 degree bends to move that stack ? Probably still not enough room. And forget about a cleanout in that vent. If the fixtur stops up it will be in the 1.5" line ,,,not the 3".

[Kristi]

... and NEVER reduce down a pipe size in the middle of the line - venting is the exact same as drainage, just upside-down. The venting is sized to go from smallest to biggest on your path to the great outdoors (the biggest pipe size of all). Air is air, that's true, but air can also be locked... you want it to be nice and direct to the roof, can offset it here and there, but still need it pitched upwards, as Cal mentioned. I like to think of venting as breathing, it takes air in and woofs it out - don't do anything to choke it off... and as everyone else said, no cleanout necessary :)

[hj]

Air is a gas, and as such, it has entirely different flow characteristics from water. It does not need or care whether the fittings are flowing the "correct" way or even if there is slope in the pipes, (as long as they are not filled with condensation).

[Kristi]

hj, I didn't mean to insinuate that air needs to be treated like water; I was simply pointing out that if you (as in the not-so-sure diy'er) imagine venting being run the same as drainage, but upside-down then you would realize how the sizing for it worked. And while you're at it, if you're not-so-sure, then pitch is certainly a good thing to have to your venting... otherwise people would be doing horrendously acrobatic things with their piping out of convenience sake, and I don't think that's a good practice to spread (imho). Here in Canada, we need the crap running downhill and the venting running uphill!!!