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basement bathroom

Posted by billnthemale (My Page) on
Thu, Nov 18, 10 at 15:23

I am wanting to put a bathroom in my finished basement and wonder if anyone has any ideas on how to run the floor drains? I have a 3" floor drain about 12" from where I want to put the bathroom and wonder if I can hook my floor drains into that?


Follow-Up Postings:

RE: basement bathroom

We had a similar situation. I think the answer will depend on where that drain connects to. If it's just a drain to a storm sewer, then probably not. If it drains into the same line that the other bathrooms in your home drain into, then it may be possible.

In our case, the floor drain connected to the main sewer line of the house. We had to break the concrete from where the main entered the house, all the way back to where we wanted the bathroom. The plumber then cut the main and put a Y type junction in. The base and one arm of the Y reconnected the original main while the other arm of the Y went to the new bathroom. The floor drain was tied into the new drain lines for the new bathroom (the old tie in was removed when they cut the old main).

I don't think you can tie main sewer lines directly into a 3inch floor drain - I'm no plumber - but that sounds like your asking for problems.

RE: basement bathroom

Thanks for your post. I think I better call a plumber.

RE: basement bathroom

We just installed a basement half-bathroom. If you can find a location for the basement bathroom that's pretty much directly under any other bathroom or half-bath in your house (regardless of what floor that other bathroom is on), your project should be much easier and cheaper. Your existing bathrooms already drain into the correct place (the sewer), so basically all you need to do is dig out enough cement to get from your new basement toilet to the nearest toilet stack.

But yeah, you definitely cannot drain a toilet into a regular floor drain. It's got to go to a toilet stack so it can drain into the sewer. Your basement sink, of course, can drain to a floor drain... just the toilet can't.

So just start by finding the toilet stacks, and if you have more than one, figure out which one is the best location for your basement bathroom. If your basement isn't finished--that is, if it just has the bare cinderblock or cement walls--you should be able to easily see the toilet stack or stacks coming down from the other floors. The stack will go straight into the cement floor. Even if the basement is finished, the stack is going to be basically directly under the upstairs bathrooms. The plumber can find it and join your new basement toilet drain to that stack. We had a basement half-bathroom installed--I mean the plumbing and fixtures alone, not any tile or finishing work--for under $1000. They had to drill out a bunch of cement but it only took a few hours.

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