[atticguy]

Hello again, (you guys rock)

I am converting my cast stack to pvc and am concerned about the transition point. I was hoping to use a PVC NO-Hub band 'donut' at the a particular cast hub but it doesn't look like that's possible. My question is:

Are those couplings reliable enough to install inside of a wall and just forget about it?

Please keep in mind that I will be discharging a half bath past the transition. I understand that I should leave as small a gap as possble (with nice clean straight cuts) between the cast and pvc within the band and then tighten to a particular torque, to minimize complications. But I'm just so darn nervous about not having access to this joint. Am I being unreasonably anal?. :confused:

Thanks again,

Louie

[RickJ]

I've got literally dozens of Fernco's No Hubs buried in walls... some many many years old.

I've never had a problem with any of them.

Heck, the No-Hubs are more reliable than the old cast :p

[speedball1]

hello again, (you guys rock)

i am converting my cast stack to pvc and am concerned about the transition point. i was hoping to use a PVC NO-Hub band 'donut' at the a particular cast hub but it doesn't look like that's possible. my question is:

are those couplings reliable enough to install inside of a wall and just forget about it?

please keep in mind that i will be discharging a half bath past the transition. i understand that i should leave as small a gap as possble (with nice clean straight cuts) between the cast and pvc within the band and then tighten to a particular torque, to minimize complications. but i'm just so darn nervous about not having access to this joint. am i being unreasonably anal?... :confused:
thanks again,
louie

Hey Louie,

You are correct to be concerned using a Fernco Neoprene Coupling on a vertical stack unless the two pipes butt together and are strapped securely.
However since you can't use a Fernco Coupling on a cast iron hub,( you must have two male ends to couple to) it's a moot question. You have only two choices to convert to PVC from a cast iron hub. One is to pour a lead and oakum joint and the other is to use a "doughnut". If it's impossible to use a doughnut, (and I don't see why not) and if you're leery about pouring a lead joint it's possible to use lead wool and caulk that in place of molted lead.
Let me know what you decide. Tom

[atticguy]

"i was hoping to use a PVC NO-Hub band 'donut' at the a particular cast hub but it doesn't look like that's possible"

I should have said, "i was hoping to use a 'donut' at the next particular cast hub but it doesn't look like that's likely, it isn't possible (ie cost/time effective) to get at the next hub. there is a LOT of stuff/utilities in the way. i will be cutting the cast iron. therefor, i will only have 2 male ends. the cast and the pvc"

My question still remains the same however,

Are those couplings reliable enough to install inside of a wall and just forget about it?

Sorry about the mix-up.

[RickJ]

For applications where I've been able to find the right one - and have plenty of room to get it on right - we've never had a problem with it afterwards.

[speedball1]

"i was hoping to use a PVC NO-Hub band 'donut' at the a particular cast hub but it doesn't look like that's possible"

i should have said, "i was hoping to use a 'donut' at the next particular cast hub but it doesn't look like that's likely, it isn't possible (ie cost/time effective) to get at the next hub. there is a LOT of stuff/utilities in the way. i will be cutting the cast iron. therefor, i will only have 2 male ends. the cast and the pvc"

my question still remains the same however,

are those couplings reliable enough to install inside of a wall and just forget about it?

sorry about the mix-up.

If I had a choice I would go for a cast iron to PVC NO-Hub Band Coupling since it's much more ridgid then a Fernco Neoprene coupling. But a Fernco's acceptable if the pipes butt together and you strap both pipes securely so they can't move. Rick's right. If the Fernco is installed correctly you should have no problems since neoprene won't deteriorate over the years.
Good luck, Tom

[berkeleydoug]

If anyone is still interested in this topic, I asked a similar question at the link below today. If anyone had opinions to share I'd really appreciate it. Thanks! Doug

https://www.askmehelpdesk.com/plumbi...ml#post2118665