[cmartin]

My next project is plumbing. Love it.

What's the proper way to penetrate a block foundation with sewer or drain lines? Does pipe diameter matter? What if the penetration is between 2 blcoks, is wall strength an issue? How to seal around the new pipe, some brick and mortar?

My last experience with this was installing crawlspace vents and I used a chisel and sledge. Not fun but it worked.

I've found some info online, but as usual you get what you pay for.



I'm trying to figure out if I should tackle this or bend over and pay the man.

Thanks for any advice

[BlackTalon]

What a horrible detail! Water will pour right through the wall by traveling through the insulation.

[EDITED] -- according to the IRC, you either need to have a relieving arch over the foundation penetration or use a sleeve that is two pipe sizes greater than the pipe passing through. So to go with the sleeve detail chip through the CMU and install the sleeve (grout it in place). Once the pipe is installed through the sleeve you will need to seal the pipe to the sleeve, and seal the pipe to the waterproofing system. Don't have the sleeve extending past the exterior plane of the wall though, as that makes it more difficult to install the flashings and creates a failure point. The sealant use between pipe and sleeve must be approved by the code officials...

Is the wall reinforced, with filled cores? If so, probably best to center the sleeve/ pipe at a head joint or in the middle of a CMU, so you will not impact the vertical steel. And keep away from the bed joints, in case they have reinforcing. If the cores are hollow, then it's easiest to just go through a core. How to find out? You can drill a pilot hole into the core from the interior of the wall.

Chisel is ok for making the opening. A 15 lb electric chipping hammer is even better. And once the pipe is run, basically fill the space around it with mortar/ grout.

How you seal the exterior penetration will largely depend on what is currently in-place for waterproofing or dampproofing. So that part can be figured once the wall is dug up.

[cmartin]

Thank you sir, very helpful.

[deutschkar]

They make gaskets for this application. There will be some epoxy/concrete parging required but there are much better ways to do this. It will require something a little more accurate than a chisel and sledge though.

[cmartin]

Thanks. There are more pieces to this than I expected. Proper pipe material, material around the pipe, insulation, depth, slope... now more tools? I always make room for more tools.

[cmartin]

Getting closer to doing this, what's the best tool to get through concrete block walls? No, I havent done the core test yet.

Hammer drill?
Rotary hammer?
Chipping hammer?
sledge and chisel?

I'll need to do at least 2 and maybe 3 holes for a sewer line. HF sells a cheap rotary hammer, think it's good for 3 holes? Or I can rent a Hilti and maybe the bit(s). Core drill or hammer it apart? I could run an air line to area I suppose.

This seems like one of the jobs a pro can do in an hour and me, harry homeowner, takes all day unless I have the right tools.

[Vicegrip]

Mid size hammer drill that is made to run for more than 30 seconds at a time. (this rules out the HF stuff)

Drill a ring of 3/4* holes with an inch to inch and a half between each hole and then use a chisel point to hog out the middle. Plan the ring holes to be a little bit larger than the needed end result. a 6 inch OD pipe make the inside edge of the holes at 6 1/2 or more.
Good padded gloves are a must if you want to feel your fingers after you are done. When you hit rebar while drilling the ring holes just skip to the next hole. Take your time and remember that the concrete needs a place to go when you are chipping it out. Start between 2 hole and blow out the material towards one hole then the other. Keep enlarging the hole by chipping out chunks. Trying to drill straight in with the chipping point does not produce much result. chip the concrete off the rebar then saw the rebar. Don't need to cut the rebar through. 1/2 cut then bend it off.

* the ring holes you drill to be smaller than the width of the chipping point. If same size or larger the chisel will end up going into the holes. you want to be able to cut the bridge between the holes without having the chisel go into the holes.

Edit. Above is for pour in place concrete. If "cinder" block just take a 22 oz framing hammer or the like and a 12 inch long by 1 inch wide cold chisel at it.

[BlackTalon]

x2 w/ VG -- for non-reinforced CMU all you need is a hammer and cold/ masonry chisel. Very easy to cut out.

[cmartin]

Thank you, great explanation. I friend loaned me a hilti hammer drill and I have a chisel in the garage, somewhere. It sounds like the excavation is going to fun part.

Thanks again, very helpful.

[cmartin]

Any reason not to use Transition Cement when connecting ABS to pvc? I've read a bunch on the interwebs and its sounds like glue works and there wont be a problem. Anyone gone through this?