Crack in Drain Stack: Looking for Options
Let me start by saying I know nothing about plumbing...
Recently, we discovered a leak along a drain pipe that flows down from a second-floor bathroom. The amount of water running down the side of the pipes when the fixtures are running is a minimal but steady flow. We have had two separate plumbing firms come to diagnose the problem and both concluded that there is a "crack in the stack" somewhere along the drop through the first floor (where it is embedded in a wall) but before the pipe enters the basement (where it is exposed). Both plumbers believe the crack is in the vertical stack and not in any of the pipes leading from the fixtures to the stack. Just to rule out other causes, we had the second plumber snake the drain pipes and the water continues to leak at a trickling rate. The stack is cast iron, and original to the house which is 82 years old.
Their proposed solution is to expose the pipe in the first floor and replace the section of the pipe (perhaps the whole piece) that is damaged. This would not be so painful to hear except to get access to the pipe, we would have to original built-in cabinets removed. There is no way to access the pipe from another angle due to a variety of structural issues (one side is cement block before you get to the wall, the other side has built-in cabinets and a 2-story laundry chute, and the third side has a series of wood studs). Both firms have cautioned that there is a good chance that we will lose the cabinets when we remove them because of the nature of the age of the built-ins (they are in great condition), and the way they have been fixed to the wall.
So we are looking for other options. I'm wondering if there are any less invasive approaches to solve this problem such as:
1. Some sort of solution or coating to pour down the pipes that could largely seal the crack, or
2. A way to guide a "sleeve" up the inside of the 4" drain pipe from the basement that would then cover that leak (pipe within a pipe approach), or
3. Some way to build a pipe around the old pipe (without opening up walls so all this would have to be done through the basement floor) by using a series of clamshell like structures and pushing them up the exterior of the pipe (the new "pipe" would have to be wider than the joints obviously for this to work).
Are there any approaches like those outlined here (OK, #3 is a bit of stretch), that might be easier fixes that would allow us to preserve the built-in cabinets and avoid the major surgery of opening up the walls?
Any thoughts or advice?
