I have a 30+ yr old house with copper piping, that I purchased 2 yrs ago. Back in May, I had a problem with my plumbing. Whenever I would use the washer, it would cause the toilet and tub to back-flow. It would start with the toilet bubbling and then the water level on both would rise until I shut off the water. I attempted to treat the problem myself by getting some main-line opener and pouring it down. Unfortunately, that seemed to aggravate the problem. Whatever was causing the blockage trapped the opener and it ate through a section of the copper piping. I had Roto-Rooter come out and they added a boot or sleeve onto the area where the drain opener had ate through. Before doing this though, the augged or snaked out the main drain line and discovered that roots had grown into my main line. A root treatment was also done and I had no trouble for several months. Then 2 months ago, it started happening again. Since the job was still under warranty due to the root treatment, I called Roto again. They snaked out the main line like before and the plumber who performed the task advised me to pick up some root treatment from Lowe's or Home Depot to prevent this from occurring again. A few days after the plumber left, the same problem started happening again. For the past month and a half, I have tried various things on my own. I have used 5-6 containers of root treatment, 7-8 of various enzymatic type drain openers and just this week I used two different types of industrial strength main line openers. The problem has gotten progressively worse. I used to be able to get way with just running a smaller load and now even the lowest setting on the washer will trigger a flood. This weekend, I rented a 100ft electric snake from Home Depot, similar to what the Roto-Rooter guy had used. After running the snake in and out several times, I came to a blockage I could not get through. I filled the tub with hot water and let it drain, using the heat to trace where the blockage began. As best as I can figure, it occurs right before an elbow shaped. After trying various attachments and running the snake in and out, I knocked lose some sediment, but not enough to fix the problem. Realizing that the problem is most likely due to a mineral build-up, I poured 2 bottles of the CLR and also a bottle of the Lime-A-Way directly down the main and waited. Unfortunately, not even that seemd to work. At this point, I am out of ideas. Short of cutting through the piping and replacing or putting a boot on it, that is. Any ideas or suggestions would qualify you as a saint in my book. Thanks.

You have a real pharmacy going on down in those pipes, stop with the chemicals. Everyone has been putting a bandage on a bigger problem. That area of the drain needs to be dug up a, cut out and replaced. You can't expect Rootx to clear a drain, it merely stund the roots and kills them but doesn't rod them out.

I think you disagree with my answer because you mistakenly believe this is a mineral build up, it doesn't sound like that at all. You said it yourself, roots are your problem and it sounds like they have opened up a significant crack in the pipe. I know you want an answer short of cuttting the pipe but I believe you are asking for yet another band aide approach to try. I am saying stop with the chemicals and band aides, find the breach where the roots enter and replace that section of pipe. This is beyond DIY for nearly all home owners.

The roots were growing into the main line OUTSIDE of the house. The blockage is in the main line INSIDE the house, at least 60-70 ft away from where the roots would be.

I am not there to see the problem so I could be off base but I believe that when you rod and can't go any further you have not hit the blockage, you hit a bend in the drain. Drop to a smaller cutter or even a 1/2" snake to see if you can get past the bend. Roto Rooter reached the roots and I can't see how a true blockage could develop in such a short time. You said "before an elbow shaped" and I think that elbow is stooping you rodding but not the blockage. Again I am not there.