Backpitched Cast Iron Pipe in Basement....uggh..

apunaha23 · 01-31-2011, 10:40 PM

Hi all, I'm new to this forum but thought it'd be a great place to get some ideas, or at a minimum, condolences.

I've posted a crude diagram of my existing basement sewer drain (unfortunately my scanner just died and I had to use this blurry photo for now).

http://home.comcast.net/~jeffcook41/...s/DSCN0702.JPG

All pipe is 4" cast iron, located below the basement floor. The house was built in the mid 70s and I am led to believe the pipe is 3-4' under the concrete floor.

I've had problems with backups at the floor drain and at the base of the toilet (bathroom on far right of photo drawing). So before a recent party, I had a plumber come out to rod out the line. While here, the plumber tv'd the main pipe out to the street (upper left of photo drawing, extending down toward the street). The good news, no roots and it all looked like it was in good condition. We also saw the 90-degree connector that came from the basement bath (bottom left of the photo drawing). As we pulled the snake back from the 90-degree tee, it dropped about an inch or 1.5" into some water. (This area is highlighted in yellow on the left side of the photo drawing). We marked the spot and the plumber said the only way to really fix this was to dig into the concrete and replace the pipe - roughly an $1800 job.

The party came and went without a hitch, but the very next day, water surrounded the base of the toilet again. I wasn't convinced that the backpitch we saw could be the cause of the basement toilet's problems, so I decided that at a minimum, I would replace the wax gasket and while the toilet was off, see if anything unusual was going on. When I removed the toilet I saw standing water in the sewer pipe - not good..

So out comes the plumber again.

This time the plumber wouldn't tv the pipe, but he did rod out this line from the toilet flange over to the sewer main (±20' from the right side of the drawing to the left side). The plumber says the reason there is standing water visible from the toilet flange is because the pipe is backpitched (area highlighted in yellow on the right side of the photo drawing - though admittedly the location of the backpitch is a total guess since we had no tv to see what was going on). This makes sense, but now my question is... what to do about it.

I'm wondering if some of you might offer comments or suggestions to help guide my decision. Of course I'd prefer to spend less money, but I also want to do it once and do it right. I've heard the ejector pump method would be the cheapest solution, but I'm not real excited about going this route. Something about having a gravity sewer seems preferable to me (until i see the bill i suspect). So here are my questions:

1. Should I go with an ejector pump solution? and if so, why?
2. If I dig up the pipe, any comments on jackhammering vs. saw-cut? Will jackhammering damage my foundation?
3. While doing all this work I figure I will install a shower drain, in addition to the existing sink and toilet. Do I need to be worried about new venting? No vents exist for the existing fixtures.
4. Would it be beneficial to consider taking the pipe outside and around the house to tap the main? This would be a long run, probably 50' or so, with the marginal benefit of adding cleanouts for my service main.
5. If I install new pipe beneath the concrete, should I replace the 90-degree tee with a 45?
6. Is there value in installing a backflow and/or gate valve between the main and the floor drain?
7. Any ideas to ballpark the cost for such work?

Thanks in advance for any help you can provide. I don't think I like my options :/

Jeff

LIHR · 02-01-2011, 08:49 AM

You already had a plumber evaluate your problem, and you,re not entirely satisfied with his suggestion. That's OK, and if that is the case I'd have another plumber come out and explain to him what's going on along with your diagram. Ask for options and the risks associated with each one, if any.

You don't want to do this wrong, as you mentioned, BUT you can not allow money to get in your way of doing it right.

My best advise is to have another professional evaluate on site and then make your decision. I know you want a quick inexpensive "On-Line" fix, but sometimes that's not possible.

There is not a worse experience for a homeowner than to have a serious sewage backup.

Just remember this: "The short way is the long way"

Docwhitley · 02-01-2011, 09:52 AM

Lets answer your questions as we go through

1. Should I go with an ejector pump solution? and if so, why?
If the system was not designed with an ejector pump and is operating with out one fine except for the pitch... why add one? I say just correct the problem... as I always say to my customer... Do you want to fix your situation or correct your Problem?

2. If I dig up the pipe, any comments on jackhammering vs. saw-cut? Will jackhammering damage my foundation?
I have a simple solution.... I try to do both when ever possible. Now the problem is that a Saw uses a Ton of water so if it is a situation where water will cause damage then the Jackhammer will be used by itself. You really need to do both to give a nice clean repair. you cut your path then Jack hammer between so the stones can be small enough to remove

3. While doing all this work I figure I will install a shower drain, in addition to the existing sink and toilet. Do I need to be worried about new venting? No vents exist for the existing fixtures.
by code yes.

4. Would it be beneficial to consider taking the pipe outside and around the house to tap the main? This would be a long run, probably 50' or so, with the marginal benefit of adding cleanouts for my service main.
I would say no. I believe cost and the lack of actual benefit out weigh any good that can come from this... T answer that question I would need to know how deep your line isat the front of the house. then the total length. the numer of turns and then the depth at the back of the house to determine if the added length will allow you to have enough fall in the pipe
5. If I install new pipe beneath the concrete, should I replace the 90-degree tee with a 45?
under ground I like Long sweep 90s... 2 45s will do the same but I believe the less connections the better
6. Is there value in installing a backflow and/or gate valve between the main and the floor drain?
depends ... do you mind cleaning poop? if not then no value... is you dont like it then if they work 1 time they are priceless
7. Any ideas to ballpark the cost for such work?
Pretty sure it will be less than a ball park. Here is the problem with asking that question. I live in a high price area and Plumbers earn $30/hr... Mike lives in medium18/hr ... and Billy Bob Lives in a low 3 cases of beer/day... Point is you will get different prices for each. Even when buying a car 3 people all pay 20K for the same car but if you ask 1 he tells you 20K... ask 2nd he tells you 28 because he adds in finance and tax and tags... ask 3rd and he tells you 400 a month... then you ask the guy who has a friend whos brother just bought the same car for 16K (fails to mention he traded his car for 6K). My point is... If you trust the Plumber and he knows what he was doing... and spoke with confidence... and you trust him... then have him do the work. If you dont then hire another person or atleast get another estimate.

ALL NAMES AND LOCATIONS HAVE BEEN CHANGED TO PROTECT THE NOT SO INNOCENT

apunaha23 · 02-01-2011, 04:37 PM

Thanks for your quick replies, especially your detailed commentary Doc. I'll likely dig it up and do it 'the right way', but I want to give due consideration to alternatives if they're reasonable. If I end up doing the project myself *shudder..* I'll post some pics to show how it goes.

Here's to another project that goes from one thing to twelve others. Cheers!

Docwhitley · 02-01-2011, 04:48 PM

Keep in mind if you leave the pipe in the ground... Anything in it... Will still be in it and if it ever springs a hole you will wonder where that smell is. I have a project now for the government that during the remodel they cut off a condensate line where they built the new walls. It has been fine for 10 years except for the constant complaints for the smell. Then they had a back up and sewage was all over the pace in the bedrooms! I traced it to these pipes that were left there... Now I am capping all of them

... In other words... Dont short cut... It is your house that you live with EVERYDAY!

proremodel · 02-02-2011, 02:42 AM

IF you don't feel like working with cast iron I don't blame you it sucks but you can do all the digging and cutting for your plumber and that will cut costs. Pretty simple if you have a worm drive skill saw. Toss on a concrete blade and cut (no water) make a few cuts then jack hammer up the rest of the floor. That way when the plumber comes in he just gets to work on the pipe.