Main sewer line prob

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Drof65

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Oct 6, 2010
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Location
Atlanta, GA
Bought a foreclosure to find the main sewer line (cast) out the house is rusted out for the entire run. Where it leaves the house I'm down about 1-1/2 ft below ground level. The line is still cracked at this point . My problem is there is an 8' square concrete porch on a cinder block foundation approx 3' high. Of course the porch is covered with a continuance of the roof. I punched thru the foundation in the crawlspace to find under the porch is full of fill.
I am wondering if I can reduce the main line down from 4" to 3 ' where the cast starts with a cleanout at that point. I was thinking I would slip the 3" PVC inside the old cast under the porch.
Any thoughts?

TIA
Randy
 
There are companies that can run a liner inside of the old pipe and make it work that way. I would not recomend downsizing the pipe size at all and I don't believe it would be up to code either. I personally would cut and dig up the old line and replace with new, there is equipment that can fit under a patio or it can always be done by hand. How long of a run are you talking about?
 
Right now I'm only worried about approx 8', the part thats under the porch. As long as it will flow outside the house I'll be happy for now as long as tree roots haven't blocked the line outside. After going thru a divorce i'm very tight on money. I just hated to do one huge pile of digging to expose the rest of the line under that porch.
 
If you do what you mentioned, sliding the 3" pipe inside of the 4" cast, solids will catch on the end of the 3" pipe and cause frequent stoppages. Am I understanding you correctly that there is a crawl space underneath the rest of the house with the drainage piping for the house run in the crawlspace? If so, then you might be able to do as you were thinking, only just use the old cast as a sleeve to route the 3" piping through and repipe from the 3" under the house to the new 3" line. But you cannot downsize from 4" pipe to 3" pipe, the resulting ledge will catch material and cause backups.
 
Thnx Phishfood, I really suspected big problems with the downsizing. but it was a thought so I figured I would ask.

At this point I suspect I will bite the bullet & start mining under that porch. I would like to keep it 4", most of the waste line was updated recently with pvc except for the main trunk.

I'm just praying the line outside will hold for a while.

Thanks a million folks!

Randy
 
Tunneling can suck.
Pretend you a prisoner of war trying to escape.
Make the hole big enough to work in.
Shore up the sides if you can and don't go in unless you have some who can pull you out in an emergency
Be careful.

Post a picture of your escape route if you can. We love pictures

Picture of a tunnel job.

004.jpg
 
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