Considering adding a basement bathroom; have questions...

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Batman

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I am a DIY-er with some plumbing experience. I was wondering if I could pick your brains about plumbing stuff. I considering the addition of a bathroom in my basement. I have an existing soil stack in one half of the basement that is cast iron going down to the floor, and a 4" clay tile floor drain on the other side. I am thinking everything under the concrete is clay tile.

I wanted to add the bathroom onto the opposite side of where the existing soil stack is (the floor drain side). The concrete around the floor drain is cracked, and the cracks extend into the tile elbow of the drain. (I am assuming this is from when someone had broken out the cistern right next to the floor drain.) I pulled the grate on the floor drain, and it doesn't appear that the floor drain has a p-trap. Is it possible that the p-trap is under the concrete on the other side of the basement where it joins the main sewer line? The house was built in the 1930s. Was it common practice to install a p-trap on a clay tile floor drain at all? I wanted to cut out as little of the floor as possible.

My thoughts right now are to cut the concrete around the floor drain enough to take the clay tile back to a part that isn't cracked, and add an appropriate fernco to join a pvc line back to add a toilet, sink, and a shower, and a new floor drain in that corner of the basement; basically where the cistern used to be. The cistern had a concrete floor that was poured higher than the basement floor and when they broke the block out, they did not finish the concrete so there is exposed soil in the basement right next to the floor drain. I thought I could break out the floor of the cistern and dig it down to the point where I could finish the concrete level with the rest of the basement once the plumbing was complete.

Anyway, I don't have any problems with sewer odors, so i am assuming it does have a p-trap somewhere. I guess my question is if it does have a p-trap somewhere along the line, would that have a negative effect on the drainage for the bathroom? The other bathroom in the house drains fine.

Also, I was wondering what I could do for adding another vent stack out the roof. Can vent stacks be routed on the outside of a building to the roof through the eave, or do they have to be within the four walls for freeze protection purposes? I live in Wisconsin and it gets pretty cold here. I have an idea for a proposed location inside the house, but it would involve going along the inside of an outside wall; through the kitchen cabinets, into the unfinished closet space above it, and then through the roof. It would be less than 10 feet (about 7 feet) from the kitchen window, but from the little bit of code I read, that could be okay as long as the outlet is 2 feet or more above the window, and it would be. I know the size above the roof (i would go 3" minimum) has to be significant due to our climate and it venting a toilet and other bathroom fixtures, but what size would be the minimum to sneak up to the roof with? Once it was to the wall (about 6 feet from the toilet; less far from the other fixtures), it would be a straight-shot up about 25 feet (that would be about a foot and a half above the roofline (roughly a 12/12 pitch).

I considered an up-pumping system, but in the end, I don't think my basement ceiling is high enough for it to work effectively for me without a considerable difference in cost.

Thanks for your thoughts and any replies. I look forward to hearing from someone.
 
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Wow, quite a few views, but not much for a response. Is it too many questions?
 
Pics and/or drawings seem to be loved by our experts. Me...I have no idea how to help you.
 
I certainly have alot of ideas, and i have been working on drawing up some basic plans to scale on grid paper as I don't have any CAD software. I would welcome any direction or suggestions someone would offer. I have to clean the area of all the clutter first. As soon as i can though, I will try and get some pictures to better explain my questions and ideas.
 
likely the floor drain goes into a gravel pit just for drainage I have seen this many times if you want to add a bathroom the best location with you were the sewer exit the building put the sump pump in that corner your bathroom draining into the pump can easily tie into the drainage to leave the building if the building sewer is as deep as the basement locate the 3 or 4 in cast iron most likely arrange your bath on that you can check the depth at the clean out outside the house but if there was a cistern the sewer likely in above the basement grade
 
Well, there are marks in the concrete where the floor was cut and the sewer pipe was installed after the basement was poured. It looks like it joins to the main sewer line, but i guess they could have just drained it into gravel next to the pipe? My cleanout where it comes into the house looks to be cast iron, and my soilstack is cast iron too, so i am not sure if it is clay tile pipe under the concrete or cast iron. i wish i had one of those video snakes so i could see for sure.

The cistern wasn't tied into the drain or the main sewer line at all. The drain was placed directly in front of it though; i am assuming in case of overflow.
 
I looked into renting a drain camera, and could not find anyone local who rents them. The ones I found were more than 50 miles from where I live and were quite pricey to rent (upwards of $150). I wanted to confirm that the drain attaches to the sewer and was not just draining into a pit of gravel.

I found a video on youtube where someone bought a usb endoscope and hooked it to his computer to find out where a plug was. He connected it to some drain rods and ran it down the line and accomplished what he was looking to do.

I was inspired and encouraged by the low cost of the endoscope, so I looked one up online and purchased one from Newegg.com for about $30 shipped. It came the next week and when I got it I tried it out. I put the scope in the end of some flexible plastic low voltage conduit that I had laying around and electrical taped it in place. I connected the camera to the computer. Installed the disc that came with the camera, and I was in business. It even has some built in LEDs to light the way that are adjustable by a little wheel on the wire. Full brightness seemed to work the best.

With everything looking good on my new assembly, I began to push it into the drain. I quickly found out that the drain does, in fact, have a p-trap. It was just dry from lack of use (which is a good thing because my basement is dry). So I pushed the 8ft piece all the way in and looked as deep as it would go, but it was not quite far enough. I had to reach my hand in a little way, but I came to where I thought it joined the sewer line. Just to be sure, I turned on the water on the basement faucet that drains into a floordrain on the other side of the basement above where the concrete showed I might be going. I saw what I thought was water, but just to be sure, my sister-in-law washed her hands in the sink upstairs and I saw bubbles. I also had my wife flush the toilet just to be sure, and I saw a quick rush of water go past the lens on the camera.

So in all, I would say it was a success. Very worth my time and money. I removed the camera and cleaned everything thoroughly and now I have a camera to check out engines and whatever else I need to see inside when I am working on them.

So far, the tie-in looks like it will be relatively easy with the drain. I have to rent a wet cutting saw and make some cuts in the floor by the drain; just enough probably to get the p-trap part off and get a good section of tile to attach to. I will also use it to cut around the wall at the base of the cistern to remove the concrete that is there somewhat cleanly. The floor isn't overly thick, so that should be easy. I am just hoping that the concrete isn't poured solid overtop of the drain pipe under the floor. Usually they bury it with gravel and just concrete over the top, but if they had a lot of concrete to spare, it could make my life a little harder.

Next, it looks like I have to finish the layout drawings and plan my venting before submitting it to the city for a building permit.

My wife's cousin is a Master Plumber and I was able to bounce some ideas off of him when I saw him over Thanksgiving (he lives on the other side of the state or he would probably be working on this with me in some capacity). I was told that I could use 1 1/2" pvc into the wall (which made my wife happy I wouldn't have to run it through the cabinets and countertop in the kitchen directly above) and get it into the unfinished closet above the kitchen where I could go to 2" pvc and out the roof. He gave me his card if I have any questions or run into any problems.

I do have some pictures and video, but I am not sure if I can post them directly on here or if I need to use a file sharing thing like photobucket or similar. Thanks for the direction so far. I am getting excited. It will be awesome to have a bathroom I can use when my wife and two daughters seem to do a good job at keeping our first floor bathroom occupied (the only bathroom in the house right now).
 
Please use this procedure when uploading photos to a thread.

How to upload photos from mobile devices:

1.Go to the thread you want to post a pic to.
2. Click your menu button, then click reply.
3. Type your response then click on "Attachments".
4. That will bring you to a screen where you will have to click "Add Attachment".
5. Pick from Camera, or from Gallery.
6. Pick the picture you wish to upload.
7. Then either add more photos, or click the send button.

From a home based computer:

At the bottom of the dialog box you used to post your message there is a box marked MANAGE ATTACHMENTS that will allow you to select and upload up to 10 photos at a time from your gallery.

If you have any other questions please let me know.

Thanks!
 
Ok. I was reading through the Wisconsin plumbing code, and now i am really confused. I was told by my wife's cousin (a Wisconsin state Master Plumber) that i could connect to the vent line that runs 3 to 4 inches above the first floor bathroom shower plumbing (all within the joists overhead in the basement). This section also serves as the vent for the upstairs utility sink and at the end of that run, the washing machine is tied in as well with an air break. When i did this plumbing with my father-in-law, it was inspected and it passed.

But Wisconsin's SPS 382.31 (4)(b)4., it states that "The connection of a vent stack with another vent may not be less than 38" above the next higher floor level where the plumbing fixtures are vented, but in no case lower than 2" above the elevation of the next highest flood level rim of any fixture served by the vent."

Right above it though, in (4)(b)3., it says "Vent stacks and stack vents may connect into a common vent header and then shall extend to a vent terminal." Is the section i am thinking of then considered a vent header? This 1 1/2 inch vent run goes up and then ties into the 3 or 4 inch vent stack out of the roof.

I trust my wife's cousin, but he hasn't physically seen the system that i have, and i might not be the best at describing it.

So i have had some time to take some photos and some video of what i have for ideas. I also have a layout that i am trying to work with, but the biggest catch so far is tying it all into the drain and venting. I am trying to get an isometric drawing together to submit with the building permit application, but i am somewhat unsure that my ideas will work. I do have a couple of limiting factors in that the clay tile drain line that i am tying into is only 5 7/16 inches beneath the surface of the basement floor, and i do have a basement window, 76 inch ceiling height,as well as an 8 inch thick block wall about 52 inches high(from the cistern that used to be there) to contend with.

My other big question is how high a sink vent has to go before it can run horizontal. My sink will be a pedestal sink with a total height of 36". I wanted to offset the drain on the wall under the sink to the left; and then have the vent come off of that to a height of about 48" on the old cistern wall, where it will go horizontal across the back of the toilet and over to where the other venting is going to be for the toilet and the shower in the void behind the shower. An e-mail from my wife's cousin mentioned it had to be 38 inches above the sink, but i am not sure why or if it is the rim of the sink, or the p-trap outlet. 382.31.(4)(b)2.c. says "A vent stack and a stack vent shall...connect to stack vent at least 6 inches above the flood level rim of the highest fixture discharging into a drain stack." In the "fixture vent" (382.31.(9)) section, only the maximum/minimum distance to the fixture vent is mentioned. Which for a 1 1/2 inch drain would be a minimum of 3 inches and a maximum of 6 feet at 1/4 inch per foot (as per Table 382.31-1)

Which leads me to yet another question, would it be acceptable to then wet vent the toilet and sink at a 3" diameter pipe between the toilet and the sink to that height of 48" and put a 1 1/2 inch adapter on it with a 90 horizontally over to the vent for the shower?
 
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Here is my rough layout. I still need to work out the angles and sizing. I am thinking 4" for toilet, three inch for wet vent, 2" for shower drain and under slab to vent for shower going to 1.5" above and 1.5" for sink and other venting because that is the size of the line that we will tie into in the ceiling.

 
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I don't know Wisconsin code, but under Florida code, you don't need the vent for the shower. The vent for the lavatory could serve the entire bathroom. And the way you have the vent drawn on the shower will not work. You would need to run over to the vent, turn up, use a sanitary tee to attach a pipe that runs to the shower drain, and then continue the vent out of the top of that sanitary tee.
 
Great, thanks! Forgive me, that was a really hasty drawing I had done in MSPaint over top of the layout I had scanned. Here in WI, I am fairly certain the shower is required to have a vent. So if i put a wye in the floor before the shower drain, I could have that go over to the vent stack in the void behind the shower under the floor? I am not sure about the use of sanitary tees here, but otherwise, it looks okay? For going to the vertical runs at the stack, are long turn elbows recommended, or am I stuck using a wye with a plug on the end? My main concern was the toilet being more or less on the end of the run. I also got another email clarifying the vent for the sink. He said that the 38" minimum would be measured off of the floor, not above the sink. It has to be at least two inches above the surface of the sink. My vent tie-in will be at least 6 inches above the sink because I wanted a good amount of clearance for the toilet tank, in case i ever had to service the flush valve or other tank internals.
 
So if i put a wye in the floor before the shower drain, I could have that go over to the vent stack in the void behind the shower under the floor?

phishfood said:
And the way you have the vent drawn on the shower will not work. You would need to run over to the vent, turn up, use a sanitary tee to attach a pipe that runs to the shower drain, and then continue the vent out of the top of that sanitary tee.
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Since i have an issue with with trying to keep the plumbing all under the floor 4" for my slab, I was planning on running 3" because it is 1/8 inch per foot as opposed to 1/4 inch per foot. Can i run a long turn 90 on the end and run it up above the concrete where it meets a 3" to 1.5" adapter above the slab?
 
Yesterday i picked up my permit. So far, all of the concrete is up and out, and today I completed the tie in for the vent before moving on to the grueling task of digging out the roughly 6' by 10' area. It is mostly heavy, wet, sticky clay and it is alot of work hauling it out with 2 5 gallon buckets through my basement window, but i am looking forward to the finished product. With that in mind, i dig on, thankful for the cooler temps right now.
 

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