Replacing old main drain pipe

[Mail Man Bob]

Old drain is at least 45 years old and has broken under a concrete slab and roots get in and clog it up every 6 months. One estimate was for $3K, which includes breaking a concrete patio, installing new drain pipe and replacing patio.

There are 2 alternates that I thought about doing instead to keep from breaking up the concrete....

1 - Slide a PVC pipe inside the old terra cotta pipe. Advantage is lower cost, but it also makes the pipe diameter smaller.

2 - Re-route a new drain pipe around the patio. This would be my first choice except that the only way is to go out 90 degrees from the original, which means either two 90 degrees bends -- or 45 degrees if that is available.

I posted a sketch the following newsgroup - the closest one I could find to plumbing...

alt.binaries.pictures.woodworking

If anyone has experience with this kind of situation, I would appreciate hearing a few words.

Thanks!

Bob

[PeterD]

There are commercial alternatives to fix this... Saw it just a few weeks ago on one of the PBS shows, they use a liner with a polyester or epoxy resin to line old drain/sewer pipes. They did a pipe from inside the house with a hole at the other end, no lawn damage or anything.

Sadly, I don't remember the name of the process, but it seemed to only slightly reduce the ID of the line. Looked very viable!

[Speedy Jim]

Google: Sewer lateral relining

Not cheap, but an alternate.

I would re-route it. You'll have to take account of the slope over the length of the new route. Use either 45's or long turn EL's. Include a Cleanout TEE brought to surface/.

You may need permit/approval from gov't agency that handles the sewers before digging.

If it be a deep trench, may need shoring.

Jim

[dpb]

Which, depending on the required extra length may leave him w/o enough drop if the present is about right which could lead to the tendency for solids to drop out and require frequent cleanouts.

I'd tend to bite the bullet and keep the shorter and straighter route but when going back make the area over the line relatively easy to simply remove what is required rather than the whole slab.

It will, after all, be another 50-years plus before one would expect further need to do anything to that line by which time it will, in all likelihood, be someone else's problem anyway... :)

The latter is good advice even if go straight out replacement...

--

[aemeijers]

Yeah- bite the bullet and replace with PVC all the way from the cleanout fitting in the basement, to the the street connection. It won't cost that much more, you will never have to worry about it again, and you should make a big chunk of it back if you sell the place. To anyone that has ever had a main sewer line fail, a fresh line in a house they are looking at is a BIG plus. That blown-in fabric/epoxy liner thing they showed on TOH only makes sense, IMHO, in an old-urban setting where it takes weeks and a fortune to get the permits and book the crews for a proper replacement. In a smaller town, it is No Big Deal. Do it in next few weeks, and the grass patch should get a good start before first frost. $3k, including replacing the concrete flatwork, would be real cheap around here, unless the total run is real short. I'd definitely get more estimates, and probably take the middle one. It is a couple days of work for several guys using some expensive hardware, so it adds up quick.

aem sends...

[J.A. Michel]

The 4" PVC line exiting my house has a pair of 45's on it. No problem with doing it that way, so long as you observe proper slope and whatnot.

[Dave in Houston]

You should bear in mind that the city sewer "tap" may be as deep as six feet which amounts to a serious trenching job. On our current room addition project we opted to route the PVC from the new bath to connect with the existing house-to-city sewer (under the back alley in this instance) since the city sewer was almost eight feet down!

[J.A. Michel]

My city sewer is 11ft down. I've got a 1/2 bath and a floor drain in the basement drained by gravity.

[Peter Bogiatzidis]

Mail Man Bob,

As I posted in my reply in abpw, take a look at

Hope this helps.

Peter.

[Mail Man Bob]

Thanks. I did -- looks like a clever idea, but way too complicated or expensive for what I'm doing. I'll look for a flexible thin wall pvc or something similar to that for this short run.