Removing Cast Iron Vent

[Mike Lamb]

I need to replace this cast iron vent stack in the attic of a bungalow. I'm open to suggestions on the best way to remove it.

It has already got a large crack/smile in it. I could break it apart with a hammer but I don't want any chunks to fall into the drain. There is a clean-out in the basement that I can open and put in a rag to catch debris but I still don't want any chunks to fall. Since this pipe is no longer round because of the crack, could I still use a cast iron pipe cutter? Or a Sawzall would be better? Thanks.

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[Jim Katen]

I need to replace this cast iron vent stack in the attic of a bungalow. I'm open to suggestions on the best way to remove it.

It has already got a large crack/smile in it. I could break it apart with a hammer but I don't want any chunks to fall into the drain. There is a clean-out in the basement that I can open and put in a rag to catch debris but I still don't want any chunks to fall. Since this pipe is no longer round because of the crack, could I still use a cast iron pipe cutter? Or a Sawzall would be better? Thanks.

Rake out the lead & oakum & pull straight up.

- Jim Katen, Oregon

[Mike Lamb]

Good idea. I'll try that first but I'm afraid the boot will trap it from above. The roof is fairly steep and we've had plenty of snow.

[Mark P]

I've only had to do it once. I went to the local tool rental store and got a pipe chain cutter. It worked great, snapped the pipe in two real clean like. Be sure the other sections are properly supported, you don’t want something falling once this section is removed. The tool was kinda of heavy and it took two of us, one to help hold it in place, while the other cranked it. Use safety goggles.

http://www.reedmfgco.com/index.html?scr ... pe_cutters

[Marc]

If it's a lead roof jack then you'll need to straighten the lead so the pipe can come up. Feel queasy about mounting a steep, snow covered roof? That's contracting! Gotta love it.

Marc

[Terence McCann]

200 MPH tape till Spring.

[MarkM]

I have had good luck with a 4" angle grinder and an .040 cutoff blade.

[Bryan]

Lenox makes a diamond blade for the reciprocating saw that works wonders on cast iron.

Bryan

[Les]

damn kids! Mongo, help these guys out!

Chew it off and be done with it.

I have used 200mph tape, couple of layers and tapped with hammer. With a little care you can keep pretty good control.

[Jim Morrison]

You don't want to be on a roof like that if it's steep and there's still snow on it. Follow Katen's advice. I'd be surprised if the boot trapped it from above because you can always force it from the attic. If that doesn't work, well...blame Katen. That's what I'd do.

Jimmy

[mgbinspect]

Well, plumbing materials use and configuration certainly isn't one of my strong points, but what the heck this may be a dumb question.

Since it has a pretty easy life just exchanging a little air now and then, is there an acceptable permanent way to repair or reline it? I know they reline underground drain lines now with PVC or a similar meterial, which would probably be too pricey here.

Just thowing it out there as a brainstorming measure.

I mean, being in the attic, is that a reasonable consideration or is there some good reason, other than aesthitics, why a well designed patch is out of the question here?... [:-wiltel]

[Jim Katen]

Well, plumbing materials use and configuration certainly isn't one of my strong points, but what the heck this may be a dumb question.

Since it has a pretty easy life just exchanging a little air now and then, is there an acceptable permanent way to repair or reline it? I know they reline underground drain lines now with PVC or a similar meterial, which would probably be too pricey here.

Just thowing it out there as a brainstorming measure.

I mean, being in the attic, is that a reasonable consideration or is there some good reason, other than aesthitics, why a well designed patch is out of the question here?... [:-wiltel]

Sure, you could just tape it up and it'd probably be good for years. Duct tape, aluminum tape, mastic tape, whatever.

But that wasn't the question. . .

- Jim Katen, Oregon

[mgbinspect]

What causes cast iron to fail in this manner anyway? I've never seen it anywhere but in stacks. Is it a material defect from the start that just takes years to manifest itself?

[Rocon]

What causes cast iron to fail in this manner anyway? I've never seen it anywhere but in stacks. Is it a material defect from the start that just takes years to manifest itself?

Sewer gases, and ureic acid. Time

[Bain]

It wasn't the question, but there are also epoxy puttys like FastSteel that are designed to seal cracks like that.

Those cast-iron pipes are a lot heavier than they look, so be careful. You'll probably have to use some kind of a band clamp just to gain purchase on the pipe and control it as you lift it up and out.

[mgbinspect]

Replacement in this application just seems like a ton of work with no appreciable return or reward other than some form of satisfaction...

[Jim Katen]

What causes cast iron to fail in this manner anyway? I've never seen it anywhere but in stacks. Is it a material defect from the start that just takes years to manifest itself?

Good question. It looks like it exploded from the inside. Expansion from frost closure & freezing?

- Jim Katen, Oregon

[Jim Katen]

Replacement in this application just seems like a ton of work with no appreciable return or reward other than some form of satisfaction...

Depends on how you get your satisfaction.

Push it up through the roof

Let gravity do the rest.

It rolls down the roof, bounces off the gutter and lands smack in the windshield of the annoying neighbor's car.

Satisfaction.

- Jim Katen, Oregon

[mgbinspect]

That'll work... in fact, I kinda like that scenario.. The most difficult part would be mustering up the, "Gosh I'm sorry, it just got away from me." [^]

[gtblum]

What causes cast iron to fail in this manner anyway? I've never seen it anywhere but in stacks. Is it a material defect from the start that just takes years to manifest itself?

Sewer gases, and ureic acid. Time

Way up there?

[mgbinspect]

Yeah, I am tempted to conclude that it's a material defect, but then, I have never seen it happen on a horizontal run - only stacks. There's got to be some fascinating explanation like maybe a lightning strike! Or, the compounding of weight of the pipes directed into the connections - like a wedge? Something....

[Jim Katen]

What causes cast iron to fail in this manner anyway? I've never seen it anywhere but in stacks. Is it a material defect from the start that just takes years to manifest itself?

Sewer gases, and ureic acid. Time

Way up there?

I guess we don't want to know what Ramon does on his roofs . . .

[Brandon Whitmore]

You tellin' me that you guy's have never suddenly had to go really bad while on a steep roof.

It's kind of like peeing in the shower-- it all goes to the same place.

[Jim Katen]

You tellin' me that you guy's have never suddenly had to go really bad while on a steep roof.

It's kind of like peeing in the shower-- it all goes to the same place.

Was it on this forum that, many years ago, a woman wrote to complain about a home inspector peeing in the roof? She even had a picture of him that looks like it was taken from across the street.

Walter Jowers had the best comment. He asked if she was offended by the urine on the roof or by the sight of a man's penis from 60 yards away.

Does anyone else remember this or am I hallucinating?

[mgbinspect]

Gee whiz, I sure hope that photo wasn't of me, from during the two year period I was away from the forum...