Replacing Cast Iron Water Closet Flange

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Mr_David

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I'm going to show you how I replaced a cast Iron closet flange using lead wool and oakum.
The Lead wool gets packed into the joint rather ten melting and pouring it in.
Much safer this way.
" Use protective Gloves when handling The Lead wool."

This particular flange was about 1" below the finished floor and required at least 3 wax seals to set the toilet.
I'm going to raise the flange flush to the finished floor.
Normally the top end of the cast iron closet bend would also be flush with the floor.
A standard cast iron flange has only 2" of depth. For this job I used an extended hub Flange.


There are other methods of installing a new flange onto a cast Iron closet bend.
There are products that use a neoprene seal and just bolt on but I have had my share of replacing those so called easy fixes.
This is not an easy fix but it will not come loose if done right.

WC flange repair_01.jpg

WC flange repair_02.jpg
 
To remove the old flange I drilled out the lead.
Be careful.
The flange hub is tapered and you can snap a drill bit.
Sometimes the existing lead seal is narrower on one side.
The closer together you can get the holes the easy it is to dig out the lead.

Now that all or most of the lead is removed the flange should just lift out.
This one I had to chip a little concrete from around the edges to remove

WC flange repair_03.jpg

WC flange repair_04.jpg
 
Set the new flange. It can be slightly above the finished floor, but to much and the toilet wont sit on the floor properly.
pack the oakum into the hub. 1/2" minimum (packed tight)
Try to keep the gap between the pipe and the flange even.
You will have to hold the flange up in place while packing the oakum.
You can install the closet bolts and a couple strips of wood to hold it flush to floor until its tight.

WC flange repair_05.jpg

WC flange repair_06.jpg

WC flange repair_07.jpg
 
I poured Rapid Set concrete in the space under exterior of flange after I installed the oakum.
The flange has a tendency to shift a little when packing the Lead wool.

You thought drilling it out was hard.
Now you start packing the lead.
Use a caulking iron. You can use an old narrow chisel or screw driver , Just grind the end flat.
Pack it tight in approx 1/2" increments. Over pack it above the end of the pipe.
Then scrap it flush to the top of the pipe.

WC flange repair_08.jpg

WC flange repair_09.jpg

WC flange repair_10.jpg
 
Normally the pipe, the lead seal and the flange are flush. This combined flush surface it where the wax seal is going to sit.
This repair needs that area filled in.
I used a short piece of 4"ABS pipe and plumbers putty to fill in the gap.
You could use more Lead Wool instead of the putty,
But after packing the flange you're probably thinking " It's time to wrap this up, set the toilet and go.

You should always install new bolts to the flange with a washer and nut.

WC flange repair_11.jpg
 
I can say with 100% certainty that I have learned something new today! Great looking work!
 
I also learned from this. What I was wondering was how long has it been since the old melted lead pots were used? :confused:
 
Great write up thanks. I have wondered how this would be done and now I know.
 
Now that was a great post. It looked like hard work but the results are a vast improvement! :cool:

Thanks for the lesson!
 
Thanks for posting this! I have never tried to replace one, but at least now I have some idea how to go about it.

You mentioned having had trouble with the boltdown PVC/neoprene replacement flanges. These are what I have used the time or two that I have run into this. What types of problems do you see with those?
 
Normally the pipe, the lead seal and the flange are flush. This combined flush surface it where the wax seal is going to sit.
This repair needs that area filled in.
I used a short piece of 4"ABS pipe and plumbers putty to fill in the gap.
You could use more Lead Wool instead of the putty,
But after packing the flange you're probably thinking " It's time to wrap this up, set the toilet and go.

You should always install new bolts to the flange with a washer and nut.

really its a tactical move.well done:)
 
that was cool..learned about the old method in college..but never actually saw it...my teacher told me his grandfather used to use this old technique.... very cool:D
 
but dera friend this technique is still being used at some places.
 
I don't use the lead wool. I actually melt the lead and pour it in. I'm a cheap ass.:D

Great post!

I have been unable to use the "pop-in" type on one occassion. There was so much buildup on the inside of the pipe that even after spending 20 mins scraping the inside of the pipe and jumping on the flange, I was unable to get it to seat far enough in.
 
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This thread was very helpful. I am doing this same repair for the first time. My flange was poorly installed and was a 1/4" higher in the front preventing my new toilet from sitting correctly. So far I have removed the flange using this method. I saw other posts saying to whack it with a hammer but I was not comfortable with that. Just kept drilling untill it came loose. Did not even break a drill. couple of questions.

1) Is there any reson to reuse the old flange? It is solid, but dirty. Will I get a better seal usinga new one.

2) Can the lead be reused? I cleaned it up pretty good, but it is still a little dirty. I am planning on melting it in. I have all the tools,respirator, and good ventillation.
 
If you are going through all that trouble you should use a new flange.

If you have all the right stuff to melt it go for it.
Packing the lead wool is much safer and probabbly not that much more time involved.
Don't foget to pack the oakum first either way.
I use this same method to install shower drains on abs pipe.
I discard the neoprene jiffy seal gasket and pack it with oakum and lead wool.
 
I've never used the lead wool, but will look into it the next time I need to do a flange replacement. Still plenty of cast flanges to change out around here.
 
nice repair. i have done the same here in chicago burbs quite a bit but i have never used lead wool before. i have a small acetylene tank on the truck for melting lead to pour the joint.
 

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