Sewer woes

[rooftop]

I have had problems with drains backing up in the house. I believe that part of the problem is the old sewer line from the house to the main in the alley. It is 4 inch black pipe that the locals call "orange bird". Not sure what the stuff is made of but I am not impressed with it. Tree roots have wreaked havoc on the stuff, growing into the joints and crushing the line in places. It is also very rough on the inside which really slows the flow of water and causes "matter" to hang up and clog the line.

I have purchased schedule 40 pvc (4 inch) to replace the line with (from the house to the fence line). I have two cleanouts to install, one near the house and one near the alley. I bought a rubber boot to join the pvc to the dreaded black stuff. My plan was to dig a trench and line the bottom of it with gravel. I am hoping the gravel will make it easier to get the proper 1/4" per foot slope and have it straight (no low or high spots).

My questions are:
1. What is that black pipe made out of and what were they thinking when they installed it?
2. The rubber boot came with two hose clamps, is it the preferred method to connect the new pvc to the old black pipe?
3. Are there any problems with using gravel in the bottom of the trench?

[Mike Swearingen]

1. Don't know what that old "orange bird" pipe is made of, but it was probably installed because it was cheaper than cast iron back then. Any sectional pipe is subject to root intrusion, and the best solution to sectional pipe root intrusion is to replace it all with glued plastic pipe (white PVC or black ABS), which won't allow roots in.
2. A Fernco neoprene rubber sleeve boot should be o.k., but a no-hub (aka mission) coupling would be better.
3. As long as there's no compaction of the ground over the pipe (driving over it, etc.), it should be o.k. in gravel, but sand might be better...nothing to crack the pipe against.
Just my opinion.
Mike

[jimbo]

Orangeburg pipe is made from cellulose fibres impregnated with coal tar. I found an internet story which indicates that there are 1200 miles of this pipe in the Empire State Building. Underground it has root problems at the joints.

[hj]

I do not know where they could put that much pipe underground in the Empire State Building, but it was never used above ground as far as I have ever heard. It was basically rolled up tar paper. After a few years it can "oval" and make a proper cleaning impossible. The joints are just pressed together so there was nothing to keep the roots out except their supposed aversion to tar.

[rooftop]

Thanks for the replies. What does a "no-hub" aka mission coupling look like as opposed to a rubber sleeve boot? What I have is basically a rubber tube that slips over the outside of the pipe.

The black pipe I have is brittle, kind of like a clay flower pot. When I dug hole for a cleanout, somone else had already made a hole in the pipe. When I scraped it with a shovel, it had a shiny metallic appearance. I am hoping that when dig the trench that the ditcher will break the stuff up in small enough pieces to be carried out of the trench with the dirt.

Thanks again for the info.

If I use sand, would it be best/necessary to get a tamper and compact the soil underneath. I want the pipe to be on a straight slope with no "hills or valleys".