# Air chambers necessary?



## Grumpyplumber

*Last guy I chatted with about this was in another state...maybe it differs under UPC by the state as well.*
*An example would be VTR...we go 18"-24" above the roof...no higher because of frost.*
*Locality makes or breaks the specific rules...but for things like vent distancing or water sizing it would be freaking awsome if we all had the same code.*


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## Ron The Plumber

VTR min 6" avove the roof, we will set them at 10" above.

Yes if we all were on the same page, that would be cool. But that will never happen.


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## KillerToiletSpider

Grumpyplumber said:


> *Last guy I chatted with about this was in another state...maybe it differs under UPC by the state as well.*
> *An example would be VTR...we go 18"-24" above the roof...no higher because of frost.*
> *Locality makes or breaks the specific rules...but for things like vent distancing or water sizing it would be freaking awsome if we all had the same code.*


VTR is limited to 12" by Chicago code, unless the roof is also used as a floor, in which case VTR must be 7'6" minimum. VTR must be one pipe size larger than the stack, but 4" minimum.


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## Grumpyplumber

KillerToiletSpi said:


> VTR is limited to 12" by Chicago code, unless the roof is also used as a floor, in which case VTR must be 7'6" minimum. VTR must be one pipe size larger than the stack, but 4" minimum.


 
*Our size for a any vent is the same as the house main, min 3".*
*Min VTR for anything else is 2".*
*In CA I guess they're allowed to break it up into smaller pipes using the D-squared divided by D-squared of the smaller.*


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## KillerToiletSpider

Grumpyplumber said:


> *Our size for a any vent is the same as the house main, min 3".*
> *Min VTR for anything else is 2".*
> *In CA I guess they're allowed to break it up into smaller pipes using the D-squared divided by D-squared of the smaller.*



Vents have to increase in size to avoid getting blocked by hoar frost.

They don't even tie their vents together down in Fl, when I visited my sister there was about twenty pieces of 1-1/2 pvc sticking through the roof, along with three three inch ones for the water closets, goofiest thing I ever saw.


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## Grumpyplumber

KillerToiletSpi said:


> Vents have to increase in size to avoid getting blocked by hoar frost.
> 
> They don't even tie their vents together down in Fl, when I visited my sister there was about twenty pieces of 1-1/2 pvc sticking through the roof, along with three three inch ones for the water closets, goofiest thing I ever saw.


 
*Just caught that...yeah..apparently many UPC states allow that as long as the area of combined vents is equivalent in square area.*
*After spending so much time working on ways to "discretely" run a 3" or 4" vent up and out it makes ya wanna scream!*


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## irate808

Im new to this site, so Im going to bring this thread back. I NEVER put air chambers on any of the houses I do. My theory is if you strap your water pipes properly, it will not hammer. Over 100 houses, and still no problems with water hammer. And I have a 10 year warranty. Also, here in Hawaii, they are not code.


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## Grumpyplumber

*It's code for me, and many other states...no choice on inspection.*


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## irate808

Wow. Im glad its not code here in Hawaii.


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## Ron The Plumber

In the Oregon code here but not required.


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