Sewer pipe bursting

[Jon Holdman]

In another thread, Chris asked:

Yes, I've heard of it. AFAIK, this is done for clay pipe, not cast iron. I've already replaced two sewer lines, one at my residence and on in a fix and flip. The bursting process wasn't much cheaper. The advantage is just that you avoid some of the digging. So, less damage on the surface.

[Ed O.]

It rambles a little bit, so ask if you have any questions.

Also, about the job we're discussing, is it under the house or in the yard?

Sewer Lateral update:
2nd time around:
Used a concrete walk behind wet saw (rented). This allowed us to minimize waste and greatly reduced the amount of concrete we had to break up. It dramatically sped things up and reduced the amount of time and labor needed to do the job.
DO not use a jackhammer as in the notes below. Much more efficient as to time, labor and materials to use a walk behind concrete wet saw.
***** BEWARE: THE GAS SAW PUTS OUT CARBON MONOXIDE. WEARING A RESPIRATOR WILL PREVENT YOU FROM SMELLING ANY FUMES. YOU MUST ADEQUATELY VENTILATE THE WORK AREA ******
When using a concrete saw, a jackhammer is not needed. A sledge or dead blow hammer will be sufficient for the minimal amount of breaking up concrete that needs to be done.
Sewer lateral notes:
Prep:

With plastic sheeting and some scrap luan, I used an air nailer to nail the luan to secure the plastic to the joists (not necessary unless basement is finished or there's a lot of stuff in the basement). I taped the bottom of the plastic to the floor with duct tape to secure it.
Try and plan where you’re going to set the dirt until you backfill. Have 6-12 buckets on and for concrete / debris removal.

We didn’t use a locator and were guessing the floor drain went straight out to the street and that the stack tied into it with a Y. We were wrong, the stack came down, and went straight towards the main line. The floor drain tied into it with a Y. The existing floor drain was 4”, we ran it in 3” - plumber’s choice.

Since we didn’t use a locator or a camera, we started where things were backing up - the floor drain. We followed the drains around the floor this way. There ended up being 2 failed spots, a 2” line from the kitchen and part of the floor drain line.

If in doubt, rip it all out. We almost didn’t tinker with the 2” lines, because we were beat. Luckily, we did, because we also found another spot that was really weak and we would’ve been hosed.

Pipe:
4” PVC main line / stack.
Floor drain 3”
Kitchen drain, washing machine drain 2”

Tools used:
Jackhammer, pry bar, dead blow hammer, air nailer, respirator, earmuffs, goggles, safety glasses, scrapers, chisels, shovels (round for digging, flat for filling/cleaning floor), tub for mixing concrete, a ****** trowel.
Have a 2 x 4 on hand for the concrete repair part.

Tips: use spray paint to mark your path during demo… it’s easy to fall off course.

Setting the floor drain: do not set it until you pour the concrete. Take a piece of pvc, the same size as what the drain is run in and cut it longways. Place this piece over the vertical pipe. Place the floor drain on top of it. When you have poured the concrete around where the floor drain is to be located, slide the floor drain into place and let it set. After the concrete is set, cut the pvc down to the appropriate level.

Things I would’ve possibly forgot:
On a washing machine drain coming out of the floor in the basement: be sure to build in a p trap underground.
Same with the floor drain - build in a p trap.
Connections to the lateral must be made with Y’s and not T’s. Use a street 22 or 45 off the Y to tie into your run to make things easier.
My plumber said it's typically a 3 day job. We did it with about 42 man hours of labor and had it all done, short 4 bags of concrete to fill in 21 hours. With a few more laborers, a bigger truck, and more buckets it could've been completed quicker. We also worked against some unfriendly variables, like a tenant horder and a warm house.
When buying the concrete, ask the employees to bring it out to the car on a forklift. They'll help load it too, which is nice after a long day.

Pitch required:

3" = 1/4" per foot, 4" = 1/8" per foot.