What is the proper distance between cast iron hangers

Cast iron hangars for what ?

tickle does have a valid question. Horizontal or vertical piping? Size of pipes? More info needed.

Hi Lopez...

They don't make "cast iron hangers"... ;) Did you mean you are hanging cast iron pipe with steel hangers?

Are we talking about residential or commercial job?

For horizontal cast iron pipe you'll want to install a hanger at every full length of pipe... near the clamp or cast iron hub. Basically, without over doing it, for every clamp/hub you install you'll want to install a hanger. That also means that you'll install a hanger at every change of direction you make.

On the vertical piping you will install a hanger at the base of the stack and install a RISER CLAMP at every floor the pipe penetrates.

To tell you any more I would need more information, OK? More info. Will allow me to present a more complete answer... ;)

Back to you...

Mark

Local code may require a closer hanger distance than recommended. My area it is every 4 feet for horizontal piping and at every floor level for vertical pipe.

PGH...

You're from Pennsylvania, right? If so, go back and check your code book on hangers for cast iron, OK?

Your own code book says 5 foot intervals is maximum spacing UNLESS using 10 foot lengths and then every 10 geet is correct spacing... see addendum a at bottom of list! It also says 15 foot intervals maximum for vertical (this doesn't make sense to me?)... ;)

Lopez, my numbers are right on, but still would like to know what we are working with here, OK?

Back to you...

Mark

Massplumber you are correct. In my haste to answer I posted 4 feet which is for PVC or ABS pipe and 5 feet is the proper support distance, though I'm sure that by supporting more than needed as opposed to supporting less than needed is preferred. Our local code has been merging portions of the IPC. If you are looking for the code standard for my area see Allegheny County Health Department Article XV Plumbing Code. There is no reference to the use of 10 foot lengths so the support intervals shall be 5 feet apart. Typically the more strict code applies to the jurisdiction in most states. Hangers and supports for Article XV can be found in chapter 9, though it's been a while since I've pulled the book. I'm sure you can find it on the interweb.

Addendums occur regularly to our code as IPC is being implemented. Website updates are available but may not be current. Not all IPC plumbing guidelines are acceptable and general PA code to meet MINIMUM requirements may not reflect the same minimums for my area so in the future download a version of Article XV if you would like to refer to "your own code book".

"It also says 15 foot intervals maximum for vertical (this doesn;t make sense to me?)..." Not that it applies to us, but wouldn't it mean that vertically 15 foot intervals the pipe would be supported? 15 foot interval max. no more than 15 feet between supports. I don't see what doesn't make sense. Article XV has supports @ each story height and base.

Hubless cast iron if 4' or less it must be supported every other joint. Length over 4' must be supported every joint. Support shall be located within 18" of joint. This is for hubless cast iron.

For hub and spigot cast iron, must be supported at 5' intervals if less than 10'. Pipe length 10', must be supported at 10' intervals.