Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Lifespan of steam piping?

First, thanks to all who responded.

On the basis of all this great information and the photos, etc., I sent an e-mail to all the other directors on the building's Board yesterday, declaring that previous management had been misinformed, and that there was absolutely no reason why the pipes in the walls wouldn't last another 80 years.

Then at 8:00 last night, I went down to the basement to do laundry and found the floor covered in water and a steady stream of hot, discoloured water flowing from a pair of supply/return risers where they entered the ceiling. More water was dripping from nearby wall areas and the top of the window frame. Can you say "cardiac arrest"?

However, it *was* raining heavily most of the day, and the rain stopped while I was down there. And to my great relief, so did the flow of hot water. After further investigation and a trip to the roof, I deduced that water pooling on the flat roof was making its way under the flashing and into the brick wall, thence to be well warmed while flowing down the outside of the steam pipes to the basement.

Not that roof & water problems in Toronto in November are "good news", but gee, that was the Best Bad News I could have wished for!!



  • Stuart Rogers
    Stuart Rogers Member Posts: 49
    How long do they last?

    I'm interested in hearing opinions on what the total usable lifespan of a low-pressure, residential steam system is likely to be.

    My Toronto co-op (25 units) was built in 1925 and has the original pipes and a two-year-old boiler. We need to do some substantial work on traps and other aspects of the system. But people are questioning how much longer the whole shebang will last, i.e., is it worth the investment. Apparently the previous management company (before my time) kept saying the heating system is "on its last legs" with the primary concern being the steam pipes hidden in the walls ("beyond repair"). A "handyman" who removed many of the rads for cleaning some years ago is said to have concluded that some pipes are in bad shape because of difficulties he had removing/replacing rads. (Note: this handyman is NOT knowledgeable in steam systems.)

    We have run for several years at 7-9 psig (I know, I know -- but that was before my time; I've been here 1.5 yrs). I've brought it down to 3-5 psig and we will crank that down as low as possible after the traps etc. are fixed. To my knowledge, there are no leaks anywhere.

    So, what do you think? Are those big ol' supply and return pipes in the walls getting ready to give up the ghost? Are there lots of 80-year-old systems out there that are having to be replaced? Is our piping likely to last 5 years or 10 years or another 80 years???

  • No idea, but....

    This building is still using their original piping and radiators. 130+ years old, and still going...


  • Al Roethlisberger
    Al Roethlisberger Member Posts: 194
    Seems to be a common question...

    ...with no set answer.

    I've asked this as well, regarding hot water, and the answer I've consistently received was: "It depends" =P

    And of course it obviously can depend. Pipes can rust through from the inside, outside, be physically damaged, have an unknown defect, etc...

    And all of this can be caused by a myriad of issues, maintenance, etc.

    I guess the only way to know would be to x-ray all of your piping and check for minimum thickness *laugh*

    But in all seriousness, I have to think that at the "100 year mark" any system is likely to start showing its areas of weakness. I hate to say that, as my HW system is approaching 80 years old.

    But see my post about "Reconditioning pipe in place":


    I think that over the next few decades, we are going to see a lot more cases where these old systems are "coming of age" and will need to be repiped. But who can afford or wants to rip out their walls and ceilings? And from an engineering and conservation perspective, why should one have to rip them all out when you technically already have the "chase" or the "guide" in the form of the old piping to reline them in place?

    I think the technology exists today, but I don't think anyone does this, except for large commercial applications.

    As these old systems age, I think the potential market for relining these old pipes will grow quite a bit.

    And since many old systems are oversized due to original gravity designs, new improvements to the environmental envelope, etc... even if one loses a small fraction of pipe cross-section by lining, it may actually be a benefit. ....but that's just speculation on my part.

    Anyway, just brainstorming. Sorry for the diversion =)

    I keep hearing of systems running for 60,70,80... 100 years and generally doing fine if they weren't absolutely abused or just suffered some catastrophic event. But my gut tells me that once you get into that 80+ year range, time is not on your side. I hope I am wrong *laugh*

    Just a DIY'er trying to learn, and improve and maintain his converted ca 1929 overhead gravity hot water system since there is no one local that can.
  • harold campbell2
    harold campbell2 Member Posts: 16
    repair an elbow at the end of the return?

    on topic, I have a small leak at the end of the return (steam unit)at the elbow (black pipe) just before it goes into the copper hartford loop. Just a homeowner, but is there any kind of goop or sealing agent I can apply to the leak to seal it?
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928

    The really old (say pre-1900) heating systems used extremely high quality wrought iron pipe that is naturally corrosion resistant and likely as close to eternal as you can get.

    After WW-I the quality of the wrought iron decreased due to a lack of proper iron ore, but the "new" welded black steel pipe kept increasing in quality to the point that it was at least as good as the lesser quality wrought.

    I'm not a steam man, but from what I read here and elsewhere, wrought iron or black steel steam piping above the water line has a very long life. Corrosion problems mainly occur below the water line, especially return lines buried in the floor.
  • This one too

    built in 1915......


    Mike's right- the piping in these systems should outlast all of us. The only thing that regularly eats these pipes is acid condensate, which is generally caused by improper air venting.

    Get the air venting to where the mains vent on an ounce or so of pressure, control the boiler pressure with a Vaporstat, make sure all the traps are in good shape and enjoy years of efficient comfort.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • Life span

    The supply mains will outlast the building. The returns depends on who and how it's maintained. Here a picture of a 55 year old supply main that was said to be at its life's end.
  • Mike Irwin
    Mike Irwin Member Posts: 2

    The steam heating system in my parent's house was installed in the late 1890s.

    It was still going strong when Mom and Dad moved out in 1999. It would probably still be going strong had the guy who bought the place not developed a fondness for Meth and sold all of the radiators, steam pipe, and the boiler for scrap to feed his addiction.
  • Jamie Hall
    Jamie Hall Member Posts: 22,898
    Personal experience

    The steam heat (vapour) in the building I maintain was installed almost 100 years ago. As noted elsewhere, the supply mains are all in excellent condition -- almost like new. A few of the radiators have developed leaks between sections at the lower nipples, where condensate sits. It was necessary to replace one of the wet returns a couple of years ago -- it was like a seive -- and I have a suspicion that the other one, which is buried, is none too good.

    Conclusion: if condensate sits in it, it will probably go not much more than 60 to 80 years. If not... it will be here long after I am.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Al Corelli_2
    Al Corelli_2 Member Posts: 395
    Al Corelli, NY

  • Chas_2
    Chas_2 Member Posts: 104
    This Section of Pipe

    is from the Bromo Seltzer Tower in Baltimore and has had steam blowing through it for over 90 winters.

    There is no good reason why it couldn't be another 90 more.

    Steam is Green.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • Tom Hopkins
    Tom Hopkins Member Posts: 552
    I'm expecting to get another hundred years

    out of my 80 year old supply lines. I cut into my header to add new radiators a couple of years ago and they were practically brand new. When I replaced the boiler last year the connected old piping looked near-perfect.

    The wet returns, however, are a different story. I've had to replace one length of pipe already and expect to make more repairs in the years to come. 80 years looks about the limit for those. But fortunately, the returns are in the basement and easy to access.

    I'm expecting supplies in the wall to last into the next century if the house makes it till then. By that time I plan to join the dead men.
    BRIANJ Member Posts: 118

    Home owner here. Ninety-four years of Broomell two pipe Vapor and still not leaking.
  • Jim_83
    Jim_83 Member Posts: 67

    Will copper returns last longer than steel?
  • Jim_83
    Jim_83 Member Posts: 67

    Will copper returns last longer than steel?
  • Water chemistry

    pH level and the acids that form in the condensate would be the deciding factor on which material will last longer.
  • Rich_19
    Rich_19 Member Posts: 2
    steam pipes

    One of the fittings on the loop that runs around the basement blew out one winter in a 80 year old system in a house I used to own. But the pipes were not pitched right and pooling water was a constant problem in this section of pipe. It used to bang like he** when the system was warming up.
  • Mark_46
    Mark_46 Member Posts: 312
    Another example


    When I removed the steam system from my home (i know, i know - some reading this are shaking their heads) built in 1924, the inside condition of the mains were quite good. Better than I would have guessed it to be. There was no flaking, mostly a brownish discoloration which is of course an indication of oxidation but those pipes seemed to have a lot of life remaining.
This discussion has been closed.