2 inch vs 3 inch vent run
- Thread starter Skudbilt
- Start date
Master Plumber Mark
Sensitivity trainer and plumber of mens souls
a 2 inch vent is more than sufficient ......
In indiana their are complete 4 bathroom homes with only one 1 1/2 vent going out the roof
for the whole system, they allow this all the time but I dont think it is enough .....
but somehow it seems to work...
In indiana their are complete 4 bathroom homes with only one 1 1/2 vent going out the roof
for the whole system, they allow this all the time but I dont think it is enough .....
but somehow it seems to work...
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Master Plumber Mark
Sensitivity trainer and plumber of mens souls
you have a good point, run a 2 inch vent up to the penetration through the roof and
then increase it to 4 inch........ we used to increase a 1 1/2 vent out the roof with a 3 inch increaser
and never had any issues
NYC always required a 4" penetration through the roof; even if the vent was 11/2" it had to be increased to 4" when going through the roof
https://codes.iccsafe.org/content/IPC2018/chapter-9-vents says
My point was that the increase should not be right below the roof if this is a really cold place. I doubt that NYC is that cold for this purpose.
Master Plumber Mark
Sensitivity trainer and plumber of mens souls
Its never been a problem to throw a 36 inch piece of 3 inch PVC through the roof flashing with half above and half below in the attic then reduce it down to 2 inch or 1 1/2 it always works just fine and dandy
very , very rarely is this gonna freeze over ,
maybe during a polar vortex lasting a week or more. you might notice a sluggish drain
but its only gonna be temporary thing...
something like a fart in a breeze
https://codes.iccsafe.org/content/IPC2018P5/appendix-d-degree-day-and-design-temperatures says the 97.5-percent value for outdoor design temperature is +2°F for Indy, and +15 for NYC.
Skudbilt
New Member
Thanks everybody. Picked up a 4 inch flashing today. Looking forward to removing the old vent chase and getting some needed space back.
Master Plumber Mark
Sensitivity trainer and plumber of mens souls
I hope you got a short scrap of 4 inch PVC laying around..
they dont normally sell that stuff in 24 inches
so you will probably have to go buy a full 10 foot length
good luck and have fun
Home Depot offers 2 ft for about half of what 10 ft would cost.
If you buy the 10 ft and cut it, the remainder could be used potentially.
I use a piece of 4 inch to hold dowel rods, extra-long drill bits, and such.
Charlotte Pipe 4 in. x 2 ft. PVC DWV Sch. 40 Pipe PVC074000200HA - The Home Depot
Find the Charlotte Pipe 4 in. x 2 ft. PVC Sch. 40 DWV Pipe PVC 07400 0200, Sch. 40 PVC construction can be used in both DWV and pressure applications when installed with application-appropriate fittings
www.homedepot.com
I use a piece of 4 inch to hold dowel rods, extra-long drill bits, and such.
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Master Plumber Mark
Sensitivity trainer and plumber of mens souls
Home Depot offers 2 ft for about half of what 10 ft would cost.
If you buy the 10 ft and cut it, the remainder could be used potentially.Charlotte Pipe 4 in. x 2 ft. PVC DWV Sch. 40 Pipe PVC074000200HA - The Home Depot
Find the Charlotte Pipe 4 in. x 2 ft. PVC Sch. 40 DWV Pipe PVC 07400 0200, Sch. 40 PVC construction can be used in both DWV and pressure applications when installed with application-appropriate fittingswww.homedepot.com
I use a piece of 4 inch to hold dowel rods, extra-long drill bits, and such.
Maybe you could sell it in your next garage sale too.... LOL
For several years, we had below-freezing temperatures for a week or more, which caused numerous no-heat calls
POI according to the old NYC code, PVC is not supposed to be exposed to direct sunlight, as it can become brittle and crack.
Good point. Ideal would be a lead flashing that covers the pipe. https://www.lowes.com/pl/roofing/flashings/vent-pipe-flashing/lead/4294524184-4294386969
Latex paint would be a good second-choice.https://www.charlottepipe.com/articles/combating-uv-degradation-in-plastic-piping-systems
If it were allowed, or if you don't care about the technical code violation, PVC electrical conduit would be good material to run up thru the roof. https://www.mcmaster.com/products/n...t-2~/rigid-pvc-conduit/?s=nonmetallic-conduit It is UV-resistant. The UV conduit is the same size as other PVC pipe, and glues into the same fittings.
Master Plumber Mark
Sensitivity trainer and plumber of mens souls
LOL...PVC is exposed to sunlight on every rooftop around our state.......
Yes, It might get brittle over time but I doubt that anyone is going
to go up on that roof and smack it hard enough to crack it..... and even in sunlight
they claim its still good for 100 years anyway...... underground it is good for 500 years or more
Now, just for conversations sake on a sleepy Sunday afternoon....................................
I have encountered many a neoprene rubber flashing that was totally worn out after less than15 years
and they leaked through into the second floor ceilings when it rained hard .......
I Had to take tar patch and smear a load of it over a number of them due to the
roof being too brittle to replace the flashing without damaging the roof itself.......
Tar patch is good for another 30 years more or less..
I figure in 30 years I should be in the ground by then....
I never said I agreed with some of the code officials; I just stated a fact.LOL...PVC is exposed to sunlight on every rooftop around our state.......
Yes, It might get brittle over time but I doubt that anyone is going
to go up on that roof and smack it hard enough to crack it..... and even in sunlight
they claim its still good for 100 years anyway...... underground it is good for 500 years or more
Now, just for conversations sake on a sleepy Sunday afternoon....................................
I have encountered many a neoprene rubber flashing that was totally worn out after less than15 years
and they leaked through into the second floor ceilings when it rained hard .......
I Had to take tar patch and smear a load of it over a number of them due to the
roof being too brittle to replace the flashing without damaging the roof itself.......
Tar patch is good for another 30 years more or less..
I figure in 30 years I should be in the ground by then....
Today, we live in a society that has found it is easier to win a lawsuit than buy a lottery ticket.
If a leak were to occur through a vent terminal, a plumber could argue that the PVC had become brittle and lost its integrity.
It was common to have a plumbing inspector fail the inspection with PVC exposed to direct sunlight, so to pass, plumbers would put NO HUB CI through the roof 2 feet above the roof for non-Promenade roofs and 7 feet high for Promenade roofs
When I installed a vent terminal, I used a caulked CI flange, and I have never seen one fail in over 57 years. Lead and okum is still the best way to ensure integrity
Charlotte Pipe 02688 4" Cast Iron Extra Heavy Roof Iron
Get your plumbing equipment in less than 24 hours. You can buy quality plumbing supplies online at 24hr Supply for quick and convenient service.
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Master Plumber Mark
Sensitivity trainer and plumber of mens souls
I never said I agreed with some of the code officials; I just stated a fact.
Today, we live in a society that has found it is easier to win a lawsuit than buy a lottery ticket.
If a leak were to occur through a vent terminal, a plumber could argue that the PVC had become brittle and lost its integrity.
It was common to have a plumbing inspector fail the inspection with PVC exposed to direct sunlight, so to pass, plumbers would put NO HUB CI through the roof 2 feet above the roof for non-Promenade roofs and 7 feet high for Promenade roofs
When I installed a vent terminal, I used a caulked CI flange, and I have never seen one fail in over 57 years. Lead and okum is still the best way to ensure integrity
Charlotte Pipe 02688 4" Cast Iron Extra Heavy Roof Iron
Get your plumbing equipment in less than 24 hours. You can buy quality plumbing supplies online at 24hr Supply for quick and convenient service.
People must be pretty nasty in New York City to sue over something like that
We never had anyone pull a stunt like this in our area......
I suppose throwing a peice of cast out the roof might be a good idea but why not just a
lead boot flashing??
when I was a kid I used to have the job of going up on the roof and installing a lead flashing on the 3 inch copper vents that
the guys installed...... the lead flashings are still working after 60 years in every home we did.....
I know the neopreme rubber ones are all going bad by now
but they were probably 1/5th the price of the old fashioned lead boots
not my problem any more
"I know the neopreme rubber ones are all going bad by now
but they were probably 1/5th the price of the old fashioned lead boots"
The cast Iron vent "boot" may cost 5 times, but they normally last over 50 years
If you're charging the right price, why not install better materials?
I did a job in 1963 when I was on a roof while helping my father.
The architect wanted a 50-year guarantee on the roof and was willing to pay for it
I used lead-coated copper and soldered the joints, and used Bronze roof drains, lead, and oakum joints
This roof will last well over 100 years
but they were probably 1/5th the price of the old fashioned lead boots"
The cast Iron vent "boot" may cost 5 times, but they normally last over 50 years
If you're charging the right price, why not install better materials?
I did a job in 1963 when I was on a roof while helping my father.
The architect wanted a 50-year guarantee on the roof and was willing to pay for it
I used lead-coated copper and soldered the joints, and used Bronze roof drains, lead, and oakum joints
This roof will last well over 100 years
