Need help with floor drain

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Electroguy

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I am remodeling my bathroom and want to put in floor drain where there used to be a shower. I have an 1.5" copper drain line with trap that is flush with the wooden subfloor. With the remodel, this location is now near my toilet. I want to install the drain because its already there.
The floor will yet receive a 1/2" layer of durock that will be bedded in thinset and liberally screwed down, followed by ceramic tile.
I don't have access to the underside of the floor. What is the best way to put the drain fixture on the end of the 1.5" copper pipe?
Thanks.
 

Electroguy

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That I know. That's why I'm asking. I know how a standard shower drain is installed, but that won't fit here; I don't have the height without some serious modifications. This was originally a shower drain that was fit into a fiberglass shower base. The whole room was completely rearranged. I don't have access from below, so everything has to be done from above. I can cut out the floor a bit around it, but would need to put something back that is really sturdy (this spot will be walked across) and I don't want tile cracking from movement or joints opening up. This drain would be there for potential overflows. I wouldn't normally go through the effort to put a drain in for this purpose, but as it's already there, why not.
I know I would need to fill the trap from time to time; that's about all the use it would receive, but I don't want to put in a crummy installation and have it fail in five years if it becomes used.
 

Geofd

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Yes, it is a 2" copper pipe; I just eyeballed it previously.
voleti is right look that up ...basically a copper water line threads into the trap and when a fixture is used weeps water into the trap I'm sure there is info you can find
 

Electroguy

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"No trap primer no floor drain"
I feel like I'm missing something. There is a P-Trap in the drain line below the floor. I want to know how I might be able to install a drain fitting onto the pipe where I don't have much vertical height to fit a standard approach. I have the 1/2" thickness of the Durock to easily work with. Otherwise, I only see cutting out the 3/4" sub-floor between the joists and building up something from there. I am trying to avoid doing all the extra work if there is something that will solve my problem. Does anyone have an idea of what might work?
 

voletl

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There needs to be a trap primer that will periodically feed water into the drain so the trap seal is constant. You cant just stick a drain on a pipe and call it a floor drain... will not work. Don't half ass somthing....full ass it.
 
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Electroguy

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I have other floor drains in the house that need to have the trap filled from time to time. I consider this normal. I will see how I might be able to add a trap primer.
Now how about my main question?
How do I get the drain fittings to go into the space available?
 

TomFOhio

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Electroguy, look up floor drains and floor drains with trap primer online. What kind of pipe do you have. There are all kinds
of drains that you can put on top of the pipe. Just make sure that there is water in the trap at all times or you will smell sewer
gas. If you have sink close they make a device where every time the faucet is turned on then water goes to the
trap and primes it. I believe you can get away with 3/8" copper for this.
 

RenewDave

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Not a plumber in your town would connect to that the way you describe it. There is no way to make it “water tight” without major mods. It will eventually rot and or mold. Trap primer....REQUIRED. My advice, cap it off and don’t flood your floor.
 

Electroguy

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Just for curiosity, and I think trap primers are a great idea, when did they start requiring trap primers? Last major plumbing work I did was in the 1990's and no one required it then. I learned most of my plumbing in the late 1960's and early 1970's; trap priming wasn't a real option at that point that I'm aware of.

So to put my drain in, I would then need to cut out the floor between the joists, drop a membrane onto the floor, rebuild the floor support around the drain, and put a standard drain in as you are not aware of any other means of doing it?
 

Diehard

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Trap primers are only required for specific applications. For example, emergency drains and for drains that may not be used, such as bathroom drains.
There are trap primer alternatives, however.
Google it and/or read the plumbing codes closely.
 

RenewDave

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We could get into the history of trap primers but that would lead us way off track. You could always put in a floor sink and tile directly to it and be done. Not waterproof, but with very little slope would handle a flood. It might look lame, but it would work.
 

Diehard

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I am remodeling my bathroom and want to put in floor drain where there used to be a shower. I have an 1.5" copper drain line with trap that is flush with the wooden subfloor. With the remodel, this location is now near my toilet. I want to install the drain because its already there.
The floor will yet receive a 1/2" layer of durock that will be bedded in thinset and liberally screwed down, followed by ceramic tile.
I don't have access to the underside of the floor. What is the best way to put the drain fixture on the end of the 1.5" copper pipe?
Thanks.
For retrofit work, it is becoming more and more acceptable to use waterless type trap seals. Trap primers are prone to failing and are a maintenance item.
Refer to the following article and read it to the end.

https://www.constructionspecifier.com/understanding-trap-seal-protection-devices/
 

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