Can you bury a check valve?

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Khirsah

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My house was built in 1957. It has a concrete block foundation wall, concrete block interior basement wall partitions, poured concrete slab. In one corner of the basement near the garage, it has underground plumbing for a floor drain, toilet and sink right next to the soil stack. I'm in the process of transforming it into a full bath, using the floor drain as a shower drain. Several years ago, I broke up the concrete and removed the floor drain. I installed a P-trap and a shower drain, and poured new concrete. I put walls and electrical up and then I got divorced. The project sat for years due to lack of time and money, but now my son is old enough to live in the basement and I want to get this finished so he has his own place down there. The toilet flange broke while doing some minor repairs a while back but I put a new half flange bracket underneath the cast iron flange to repair it enough to use. So now here's my question... I'm looking at breaking up the concrete again to replace that flange as well as the sink flange. I also want to install a check valve on the shower drain (formerly floor drain) to prevent sewage from backing up into the shower like what happened to my dad's property. Can I bury a check valve underneath the concrete slab of my foundation or does it need to be accessible? And a follow up question: If I cannot bury a check valve, what would be the appropriate thing to do in order to safeguard and finish my bathroom? I live in Lansing, Michigan.

Thanks in advance, I really want to get this project restarted and finished.
 

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No you can't bury a back water valve why can't you install it and use some sort of cover for access, best way to do that is put the back water valve on the branch main that way all of your basement fixtures are protected
 
No you can't bury a back water valve why can't you install it and use some sort of cover for access, best way to do that is put the back water valve on the branch main that way all of your basement fixtures are protected
All of the plumbing for the three drains are run under the concrete pad. The soil stack also connects to these drains (as well as a 2nd floor drain by the stairs) underneath the concrete as well. I have no idea how I would plumb anything to be accessible under 6 inches of concrete. I do know that there are basement showers and bathrooms installed in modern houses with concrete floors all the time...I don't know how they run their plumbing though which is why I am asking.
 
No you can't bury a back water valve why can't you install it and use some sort of cover for access, best way to do that is put the back water valve on the branch main that way all of your basement fixtures are protected
you can actually see part of the soil stack in the 2nd photo. It's to the far right of the toilet flange inside some wood framing. I did install an access cover to reach the cleanout there.
 
If you used one of those, which looks like the valve assembly inside my shop vac, and you had a serious sewage back up, wouldn’t it just come up through the toilet or some other fixture down there?
You would need to install a backflow prevented on each drain. Ultimately, any backup from the sewer will cause a problem someplace.
 
You would need to install a backflow prevented on each drain. Ultimately, any backup from the sewer will cause a problem someplace.
Which is why they are generally located in one place on the main line as opposed to a branch. At least that’s my guess..

I believe some local jurisdictions in Michigan, that were in lowing areas and thus were prone to these kinds of backups when under heavy rains, would install these or at least recommend installation of these in residential homes on the main line.
 
But while those will prevent a sewer backup from coming into the house from the main sewer, it will not prevent sewer backups coming into the basement from that house in the event of a lateral blockage.
 
Backwater valve has to be accessible. Some sort of removable cover would be acceptable.
I am not sure how I would do that when everything is surrounded by concrete. Even the soil stack is right next to the concrete wall. There's no way for me to run any sort of line to the soil stack without going through concrete or raising everything above the slab which I can't do because then I wouldn't have headspace. How are basement bathrooms installed in modern houses? Do they even have check valves in them?
 
The backwater valve is buried but is accessible from the top through a service cap that’s flush with the floor.

Look it up and read the install instructions. Your slab will need to be broken and the ground excavated.
 
Wow, I didn't see all these responses earlier. Thanks for the dialogue. I suppose I could put something in the floor as long as it ends up flush with the tile I still need to install. Someone mentioned a lateral blockage...what happened at my dad's property was the main sewage line going out to the septic tank collapsed due to age and we didn't notice it. We ended up having my uncle stay there and after about a week of using the toilet regularly, the sewage backed up into the shower due to the collapsed line. We cleaned it up and put a check valve on that line (It's a 1st floor bathroom so the plumbing is accessible under the floor joists in the basement) and had a licensed plumber come out and replace the main line to the septic tank. I just want to make sure that doesn't happen with this project. But I live in a city with a regularly maintained sewer and I can have my main line cleaned or jetted as needed. So am I just being over protective? Do I need to really do anything at all? Because right now, it's all assembled and buried from where I stopped years ago. If I don't have to bust everything up to put in added protection, that'd be great. I don't have to replace the toilet and sink drains either, I was just going to do it because I planned to bust up the concrete anyway.

I do apologize for posting in the plumbing code section...initially I was just curious what the code said about burying check valves, but now this thread has diverted more towards general plumbing questions...sorry about that.
 
The backwater valve is buried but is accessible from the top through a service cap that’s flush with the floor.

Look it up and read the install instructions. Your slab will need to be broken and the ground excavated.
Thanks for the explanation. I wasn't aware they did it like that. I broke the pad years ago and dug out the sand when I replaced the floor drain with a shower drain. Put all the sand back and poured a new section to replace the concrete I broke up. I'm just trying to decide if it's worth doing it again, and if so, how to do it in a way that conforms to code so that everything is aboveboard. I don't like jury-rigging things. But if I do end up having to put a valve in, I'll likely break up a significantly larger area and excavate so I can expose all the plumbing and lay out the new pipe correctly.
 
Back water valves are designed multiple ways but cannot be on the main because that would cause bigger issues if not installed in the right place. Where they should and can be in on each drain branch or body or on the main branch that connects towards the main line. Try looking up the ABS ones the flappers are lighter and get less clogged which will make you life much better trust me.
 
Is the house on septic instead of city sewer?

It's far safer/better to just have a well designed and well maintained septic tank and lateral lines than trying to install a check valve as that would just cause more problems like people are saying.

That's interesting that your house is made very well with so much concrete slabs and blocks yet you are on septic. Usually I would expect a wood built house to have septic being out in more rural area? Or was it your dads house only was septic and had a sewage flood from the septic but you are on city sewer but still worry?
 
Is the house on septic instead of

Is the house on septic instead of city sewer?

It's far safer/better to just have a well designed and well maintained septic tank and lateral lines than trying to install a check valve as that would just cause more problems like people are saying.

That's interesting that your house is made very well with so much concrete slabs and blocks yet you are on septic. Usually I would expect a wood built house to have septic being out in more rural area? Or was it your dads house only was septic and had a sewage flood from the septic but you are on city sewer but still worry?
My dad's house is on septic. The main line out to the tank collapsed due to age and caused sewage to back up into the newly installed shower. We put a check valve in to prevent that from happening again. MY house is on city sewer. My basement bathroom is half finished and I'm just wondering if it's worth trying to protect the shower in the same way and if I should modify things now before I finish the project or if I should just leave things as they are. If there is no reasonable way for that shower to back up, I won't worry about it. But if code calls for some sort of protection, I want to put it in. The plumbing in this particular room in my basement is buried under the concrete slab of my foundation.
 
backwater valves should only be used when they’re absolutely necessary because they’re often the SOURCE of problems.
 
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