Cracked PVC elbow in concrete - repairable without breaking up concrete?

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Hi everyone

I have a cracked pipe as seen in the picture. Can I repair it without breaking the concrete?

Thanks
 

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Short answer is "no".

Longer answer is "not reliably".

Even longer answer is "there is a lot that can go wrong with not fixing it right, and you really don't want sewage flowing onto your basement floor."
 
You could repair with this stuff and I have used it before in several situations but I wouldn’t use it in the situation you have.

Do I believe this product would work ? Yes I do. How long would it last ? I’m not sure but it wouldn’t last longer than a fitting that has not been repaired. I’m comfortable saying that.


This stuff is extremely strong.
https://weldon.com/products/810-a-b-kit/
As a test with left over product mixed up from a repair I did use it on, I took two 1.5” pvc sch 40 pipes and butted one into the side of another without contouring……I applied tension to hold the two pieces together with a large clamp. I filled the joint and built it up and let it dry.

Once dry I stood on it with all my weight, 200+ pounds and it held me.

I threw it in my garage and found it 2 years later, took it out and stood on it and it broke.

It’s pretty amazing stuff. I used it for a drywall screw hole in a 4” pvc pipe. The only way to replace the pipe would’ve been to remove some custom 12” crown molding and possible cut out some framing.

I drilled the hole out a tad larger than the rusted out screw to insure a clean surface. Then filled it with that epoxy. Waited 3 days then came back and roughed up the outside and put a second coat on to build it up. Worked great and it’s still working.
 
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Is there a Mission style of clamp that will go over the O.D. of the ends for a temporary repair?
Whether the jagged edges will catch debris or not is unknown.

I can't see in the photo, but if there is pipe below the floor, before the next fitting, opening the floor for that won't be hard since you only need a small area to drop in a new coupling. Cut off the bad with an internal pipe saw so you don't need a big hole for a saw or cable saw.

For the hole, possibly rent a 5" or 6" core drill. It'll slide over the existing pipe. Maybe even a Socket Saver or RAMBIT will be helpful to you.

Paul
 
Is there a Mission style of clamp that will go over the O.D. of the ends for a temporary repair?
Whether the jagged edges will catch debris or not is unknown.

I can't see in the photo, but if there is pipe below the floor, before the next fitting, opening the floor for that won't be hard since you only need a small area to drop in a new coupling. Cut off the bad with an internal pipe saw so you don't need a big hole for a saw or cable saw.

For the hole, possibly rent a 5" or 6" core drill. It'll slide over the existing pipe. Maybe even a Socket Saver or RAMBIT will be helpful to you.

Paul
I am finishing my basement. I need a permanent solution. What is cracked is the elbow fitting which is under the concrete. Does your solution apply for the crack like in the picture?

Thank you.
 

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These two pictures don’t look like the same piece to me.

IMG_6315.jpeg

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Why did it break? Tension on the joint or did it get hit with something? Did you try PVC solvent and cement?
 
I am finishing my basement. I need a permanent solution.
If you're going to all of the expense & work of planning & building the finished rooms, it would be wise to break the floor and replace as needed. The happy side, is that you don't have to do a pretty job of patching the floor because it will be under the finished floor. (And you can possibly even re-route to suit your plans better.)

Breaking & fixing won't be difficult. Perhaps stream water while saw cutting with a masonry blade in a circular saw to make a nice rectangle. Cut part way through the concrete. Then break with a heavy hammer and cold chisel. It'll go quickly & the mess will be minimal due to the water stream.

Paul
 
Finally I managed to break it. Turns out I need to use short pipes on 2 inch right end and 3 inch left end. Replacement should be exactly in the same spot. Any suggestions?
Thank you.
 

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You could repair with this stuff and I have used it before in several situations but I wouldn’t use it in the situation you have.

Do I believe this product would work ? Yes I do. How long would it last ? I’m not sure but it wouldn’t last longer than a fitting that has not been repaired. I’m comfortable saying that.


This stuff is extremely strong.
https://weldon.com/products/810-a-b-kit/
As a test with left over product mixed up from a repair I did use it on, I took two 1.5” pvc sch 40 pipes and butted one into the side of another without contouring……I applied tension to hold the two pieces together with a large clamp. I filled the joint and built it up and let it dry.

Once dry I stood on it with all my weight, 200+ pounds and it held me.

I threw it in my garage and found it 2 years later, took it out and stood on it and it broke.

It’s pretty amazing stuff. I used it for a drywall screw hole in a 4” pvc pipe. The only way to replace the pipe would’ve been to remove some custom 12” crown molding and possible cut out some framing.

I drilled the hole out a tad larger than the rusted out screw to insure a clean surface. Then filled it with that epoxy. Waited 3 days then came back and roughed up the outside and put a second coat on to build it up. Worked great and it’s still working.
I'm not a plumber....but I used to own a PVC millwork manufacturing business and I know a lot about adhesives used for PVC. Your suggestion of possibliy using Weld-On 810 is a good one. Weld-On 810 is not an epoxy. It is a type of adhesive called a methyl methacrylate. Methyl methacrylates are 2-part structural adhesives that are acrylics. These are absolutely excellent adhesives for use on PVC and they are structual. They are as strong as the PVC material itself and can be built up in the same way as you would build up putties and patching materials like Bondo, except methyl methacrylates are exponentially stronger and the bond to clean PVC is exceptionally strong. With a PVC waste line not being pressurized, using Weld-On 810 would work well, but perhaps a better adhesive to use because of the method of application.....a caulk gun.....would be PVC TrimWelder by Fuller.

https://www.amazon.com/TrimWelder-L...703636850&s=industrial&sr=1-7&ts_id=401543011
You would need a twin-tube caulk gun to apply it. Here is an inexpensive one that would work fine.

https://www.amazon.com/Component-GD...0+ml+twin+tube+caulk+gun,industrial,88&sr=1-5
With TrimWelder and a twin 200ml tube caulk gun, you could precisely apply a thick bead of adheive on the edges of the pipe to be joined back together. Then, you could apply ample adhesive on top of the crack around the circumberance of the pipe, smear the adhesive, and embed fiberglass cloth in the adhesive with a disposable putty knife. Then apply an ample amount of more adhesive over the fibeglass cloth and and butter it/even it out/smear it with the putty knife, so you end up with a substantial built up patch of the TrimWelder adhesive, reiforced with fibeglass. I'm quite certain that would never leak.

TrimWelder sets quite quickly.....15 minutes and it is dry in 45 minutes. a static mixing nozzle (2 provided with the adhesive) is used to mix the adhesive automatically as the 2 parts come out of the caulk gun. You need to work quickly ...... 10 minutes or less..... before the adhesive starts settin up in the nozzle. If it sets up, you discard the nozzle and you stick a new nozzle on the gun. Because you might need to make 4 or 5 applications of adhesive in your patching process, because you'll be working to stabilize the pipe in the different stages of adhesive application, you should buy 5-10 extra nozzles so you have extras in case the adhesive sets up in the nozzle you're working with.

https://www.amazon.com/Mixing-Nozzl...tatic+mixing+nozzle,industrial,94&sr=1-4&th=1
Your most important step will be the first one where you are applying a bead of adesive the the edges of the break in the pipe. You may have to sit there for 20-30 minutes holding the sections of pipe together to allow the bond to take hold if you are not able to devise a way for the loose section of pipe to be held steadily while being glued to the part of the pipe embedded in the concrete. Once that first bond is holding, You can easily do the buildup of adhesive and fiberglass cloth around the circumferance of the pipe without having to worry about the pipe moving around.
 
You’re right it’s not an epoxy.


To the OP :

Cut that fitting out and replace it
 
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