Replacing Old Rusted Galvanized Pipe Under Foundation

JLW2099 · 03-29-2012, 09:14 PM

I have a nasty little problem. The main drain from my kitchen sink, which somehow ties into the washing machine, has been clogged for a little while. The kitchen sink doesn't drain and the washing machine backs up into the kitchen sink. I've tried using my 75' electric snake to unclog the drains to no avail. From the washing machine access port the snake will travel close to 30' and then binds up. When I pull it out, I find that there is no debris hooked to the spring. I've tried pushing through with a spade bit and root cutter, but thats not working either. So I then tried the kitchen sink access port. There the snake would only go about 3' in before hitting dirt. Obviously, that was a broken pipe at the elbow. So I excavated that pipe about two feet into the house and through the foundation. I was right about the pipe being broken at the elbow, but now I see its not just the elbow but the entire vertical pipe (leading to the sink) and the horizontal pipe (leading to the septic system). The bottom of all what I can see/feel is rusted out and crumbling. So at this point I have to figure that the entire length of drain pipe is gone at the bottom and I probably wouldn't be able to snake it with any degree of success without opening it up even more.

So my questions are:

How does one go about replacing a main drain that runs under the foundation of the house? (dig a tunnel, try to sleeve it, cut into the foundation more, etc...)

IF the foundation has to be cut open, since this pipe goes all the way from front to back under it, would it have to effectively be bisected? And if so, how do you ensure that the two foundation halves won't separate slowly over the years and cause structural damage to the house?

Is it normal, or against codes, to have a washing machine drain tied into a kitchen drain?

My apologies for the long info at the beginning, but the more info one has, the better. IMO it always helps to bring more sound advice.

Thanks in advance for any help/advice you might lend.

joecaption · 03-30-2012, 01:16 AM

Not many choises, the floors going to have to be cut out and new PVC lines ran.

LateralConcepts · 03-30-2012, 01:41 PM

I would first get a camera down the 4" cast iron main line (building drain) to see the extent of the deterioration. If the bottom of the old cast iron sewer line is rusted out and leaking wastewater into the surrounding soil, it's a problem that shouldn't be ignored. It will eventually lead to soil erosion possibly damaging the foundation. Likewise, causing pollution, mold, potentially contaminating water sources, etc.

I don't know the layout of your home, but then there are a couple options. Lining or Bursting to be less intrusive, avoid concrete demo, and extensive excavation. Check with local plumbing contractors in your area. Lining may be the best solution. A resin saturated, fiberglass liner is blown into the old pipe. A calibration tube holds it tight against the interior walls of the pipe while the resin cures. Once it's dry, the cal tube is pulled leaving a newly lined pipe. The problem then however, depending on the location and number of other lines tying into the main, is you have to open those back up. If you choose the right contractor, they should have cutting tools to do that. If you search "pipe lining" or "sewer lining" on YouTube, you'll find a lot of videos that explain how it works.

jammin06 · 03-31-2012, 03:07 AM

Is it a finished basement? You don't absolutely have to follow the old line.
Can you run new pipe up inside floor joists across the house and then go down?
If so, even breaking into a basement ceiling would be easier than breaking through the concrete floor all the way across the house.

And you will be using ABS pipe, not PVC.

As long as the pipe is sized and vented correctly, no problem with washer and kitchen together.

(just down I-90 from Coeur D'Alene in Greenacres )

JLW2099 · 03-31-2012, 06:46 AM

Thanks for the tips/ideas.

Unfortunately, this is a single floor house and it all runs under the foundation. So no luck as to having something as simple as a new pipe through the rafters or joists.

And that was my bad for saying PVC when I meant ABS. As for re-lining the pipes, I came to the same conclusion when I found a Youtube video mere moments before I checked back here. Its a major relief to know I don't have to give my house some major surgery now. At this point, all I need to do is rebuild/reinforce the exposed pipe enough to snake the drain without the opening falling apart, snake it, the reconnect to the sink, and get someone out for the re-lining. Personally, I'd love to do this myself, but this would be best done by a pro.

Thanks again guys.

Oh, and here is a link to the video I found (thats really detailed) for anyone else who might find this in the future and have the same problems.

http://youtu.be/CnZ_9ctQpBc

rjniles · 03-31-2012, 08:19 AM

Quote:

Originally Posted by jammin06

Is

And you will be using ABS pipe, not PVC.

Why do you say he must use ABS? PVC is used in many areas of the country for drain pipe. In fact it may be more common than ABS.

In my area I can get PVC anywhere, I would have to hunt for ABS

LateralConcepts · 04-01-2012, 11:00 PM

Quote:

Originally Posted by JLW2099

Thanks for the tips/ideas.

Unfortunately, this is a single floor house and it all runs under the foundation. So no luck as to having something as simple as a new pipe through the rafters or joists.

And that was my bad for saying PVC when I meant ABS. As for re-lining the pipes, I came to the same conclusion when I found a Youtube video mere moments before I checked back here. Its a major relief to know I don't have to give my house some major surgery now. At this point, all I need to do is rebuild/reinforce the exposed pipe enough to snake the drain without the opening falling apart, snake it, the reconnect to the sink, and get someone out for the re-lining. Personally, I'd love to do this myself, but this would be best done by a pro.

Thanks again guys.

Oh, and here is a link to the video I found (thats really detailed) for anyone else who might find this in the future and have the same problems.

http://youtu.be/CnZ_9ctQpBc

That is an excellent video. I've watched it a couple times before.

jammin06 · 04-02-2012, 03:15 AM

Quote:

Originally Posted by rjniles

Why do you say he must use ABS? PVC is used in many areas of the country for drain pipe. In fact it may be more common than ABS.

In my area I can get PVC anywhere, I would have to hunt for ABS

my bad