Vent piping

[Eng_Plumber]

In the wast or soil venting.
assume that i have a branch serving a number of fixtures. I know that I can vent the branch instead of venting individual fixtures. In case that the drainage piping in buried under the floor, Can I put my vent pipes under the floor too and move to the nearest wall to achieve the required 6" above the flood rim level that required by the national plumbing code

 

[phishfood]

No, the vent needs to rise vertically from it's point of attachment to the drainage line it serves until it is the 6" above the rim of the fixtures.

 

[Eng_Plumber]

But in the National Plumbing Code I found the item below




What he mean by (underground vent piping)??
does he mean buried pipe?

 

[phishfood]

That means pretty much what it says.

The minimum size of vent pipe that can be installed underground (buried, covered over by concrete, etc) is 1 1/2".

Not being familiar with National Plumbing Code, I hesitate to comment too much.

But if I understand your question correctly, you will need to find a point that the drainage line in question passes under a wall. The vent connection should be made at that point, and rise vertically up into the wall.

 

[Eng_Plumber]

I understood the following,
The vent piping can not be installed buried horizontally underground but it should be extended vertically 6" above the fixture rim from the point of attachment...right??

If it so,...Why the code mentioned (underground vent piping)?
It is supposed that the vent piping can not installed under the ground...as I understood

For more clarification I attached a CAD file contain a simple drawing of a soil vented piping...but the vent piping is supposed to be wrong as I installed them buried under the floor. Kindly show me the correct vent pass on the same CAD file

PL-DR.dwg

The green line represent the vent piping
The magenta line represent the soil piping

 

[Eng_Plumber]

kindly comment on the CAD file....and please clarify What meant by the word (underground vent piping) as the vent can not be installed underground....as I understood?

 

[phishfood]

Due to a really poor internet connection, I am not able to view the file.

Vent piping may be installed underground, as long as it conforms to all codes regarding vents.

Perhaps the file that you have posted the link to clears it up somewhat, but without being able to view that, I am not sure what your question is. Hopefully someone else can view the file and comment.

 

[Eng_Plumber]

Thanks phishfood for your help.......But you said above that (the vent piping may be installed underground as long as it conforms to codes)
O.K....what is the longest vent pipe that can be installed underground?

 

[johnjh2o]

Has anyone been able to see the cad file? I haven't been able to load it.

John

 

[Eng_Plumber]

This is the same file but in anther uploading sites

MEGAUPLOAD - The leading online storage and file delivery service

PL-DR(1).dwg - download now for free. File sharing. Software file sharing. Free file hosting. File upload. FileFactory.com

http://www.mediafire.com/?3z5day1nibe41c3

 

[havasu]

.dwg is a file that is unacceptable for most folks unless they convert to another type of file, such as .pdf or .jpg. Is it possible you could transfer to a .pdf file, so other could view your image and assist you?

 

[Eng_Plumber]

Thanks havasu 4 your help....Kindly find below the same file in pdf format

MEGAUPLOAD - The leading online storage and file delivery service

PL-DR_2.pdf

request download ticket | PL-DR_2.pdf - ifile.it

 

[havasu]

I believe I finally got it for all.

 

[johnjh2o]

If the green lines are vents you can not run them horizontal below the flood rim of the highest fixture.

John

 

[Eng_Plumber]

Good...But in the national plumbing code I found the item below which mean that the vent piping can be installed underground......and this is what i can not understand

 

[johnjh2o]

What they are referring to is vertical vents. Take a look at your drawing. What would happen if you had a main line stoppage? All your vent lines would become filled with sewerage. After you get the main line cleared the vent lines now have paper and other debris in them that was left behind from the stoppage making them useless. With no way to clear them. That is just one reason why it is not allowed.
Also in your drawing I see no waste or vent lines for you sinks.

John

 

[Eng_Plumber]

OK John.....Now I believe that the vent piping can not be installed horizontally. But the code is speaking about underground vent piping....and the word -underground- means that the pipe is horizontal....

Does the code means that the vent piping can be installed under the ground but with a limited distance to reach the nearest wall and then rise vertically ?
I mean that I will vent my sewage pipe and move horizontal underground to the nearest wall and rise the 6" above the fixture rim......can this be accepted??

According to my drawing i cleared the sinks wast to simplify the drawing

 

[johnjh2o]

No you can not run a vent horizontal even if it is above ground unless it is 6" above the flood rim of the highest fixture. Looking at your drawing saying north is up. Where your waste line passes under the partition at the 2dn. and 3rd. toilet if you put a vent at that point and ran it up the wall and tied it into your other vents over head it would be fine. You could also do the same thing on the next three toilets. Then do the same for the last toilet. Just keep in mind that no vent can be run horizontal below the flood rim.

John

 

[Eng_Plumber]

Thanks John for your interest but ......

what about the word (underground vent piping) that mentioned in the code?

 

[johnjh2o]

That would be the section of vent that is vertical before it comes through the slab.

John