Toilet flange & bend

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Joined: Thu May 29, 2014 6:20 pm

Toilet flange & bend

Post by susanmartin7007 » Thu Jul 10, 2014 3:27 am

Hi Shannon,

Working on a one story 1970's ranch with 1 bathroom.

I need to remove the toilet and then remove the cast iron 90 degree elbow that connects the toilet to the waste line. It failed at the bottom of the bend and all has been professionally cleaned and sanitized. My concern is the old existing elbow is connected to a newer black plastic waste line pipe and where they come together there is a rubber connector with two tightening rings. If I crawl under the house and unhook the rubber connector, how do I get the elbow out of there so I can replace it with new? The videos I have watched show people beating it out with a hammer and that method didn't work very well.

Second, the videos make it look like the new elbow is dropped in from above through the hole and sits on the vinyl floor without any bolts or anything.

Also, once I put the new elbow in, do I just connect it to the existing waste line with the same rubber connector as long as it is all snug? Do I need to use any sealant or?

While I am under the house I need to also replace the waste line from the kitchen sink as it is leaking and I believe is also cast iron. It comes through the floor, angles about 25 degrees and then travels 30 ft where it hooks into the main waste line.

There is room in the crawl space (barely)to crawl and roll over, etc and the pipes are exposed completely since the insulation was removed. Nothing is buried that I can see. It's all hanging from those metal tie things and fairly easy to reach. The house is vacant so no water is being used presently.

Last, I need to install new insulation under there. Do I use the insulation with paper backing or is there special insulation for that? Do I use the string to hold the insulation up or is there a more efficient method? I saw a video where they stapled up the string first then went back and inserted the lengths of insulation. Took a long time with one person skootching around under the house.

Do you have any advice before I tackle this project? Is there something I need to be careful not to mess up?


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Re: Toilet flange & bend

Post by Shannon » Thu Jul 10, 2014 4:14 pm

Hi, I moved this topic into the plumbing category instead of electrical, you must have posted it there by mistake .
When you loosen that rubber fitting under the floor it should slide off of the cast pipe and over completely onto the ABS (black plastic) pipe. The cast elbow and toilet flange should all be replaced at this time , so really everything from the rubber connector up to the toilet. Once the rubber connector is removed then you can remove the screws or bolts that are holding the flange to the floor in the bathroom. You maybe then able to simply pull the flange up off the floor and the elbow and any pipe should come with it. It maybe necessary to cut the cast pipe below the floor before things will come out. Be careful because cast is heavy .
Now you will need to buy new ABS components to get things all hooked up again. From the sounds of it you need a toilet flange, 90degree elbow ,maybe a bit of pipe and a butt connector ,also some ABS solvent cement (glue). These should all be 3" in size. You should be able to cut and fit all the pieces together to fit your situation and then glue everything together including the new products to the old ABS so the old rubber fitting will not be needed. I have many videos covering a lot of the things you need to deal with for this job so please check them out.
For your sink drain it will take similar products but in a smaller size, probably 1-1/2" ABS. You will not find any 25 degree elbows but should be able to find a 30 degree and that will work since you are going such a long distance. Be sure that pipe traveling the 30' distance has a slope of about 1/4" drop per foot of horizontal travel so it drains properly.
Any batt style insulation will work in the floor and usually string, string mesh or strips of thin wood fastened to the bottom of the floor joists is what is used. It is tedious an some times just a helping hand is all that is needed to make it go better.
Good luck!
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Posts: 12
Joined: Thu May 29, 2014 6:20 pm

Re: Toilet flange & bend

Post by susanmartin7007 » Sat Jul 12, 2014 1:48 am

Ooh. I forgot about the 1/4" per foot drop. Thanks!

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