You need a flange extender, not spacers.

Here is a link that might be useful: Flange Extender

Used the wrong word should be extender. Thanks for the link that's just what I have. My question is if silicone alone is sufficient to hold them in place? I can't see how I'd screw them down short of drilling/tapping the cast flange.

You are not required to screw the flange extenders down. The flange extenders are laid on top of the flange, then the closet bolts are secured under the flange in the normal manner, passing through the slots in the flange extender and through the base of the water closet bowl. When the nuts are tightened it pulls the flange upwards maintaining the flange extenders in a sandwich between the existing flange and the bowl. As a rule, i apply a layer of clear silicone on the top of the existing flange before installing the flange extender, but that is not a requirement. Most of the flange extenders have a rubber gasket material firmly affixed to their underside.

there is nothing wrong with 2 wax rings. It worked on your application before. That is what I would do.

Not worth the risk in my humble opinion. Stacking wax rings can be trouble if they don't squash together evenly, which can happen very easily. Also, more likely to eventually blow out a weak point.

QUOTE;"there is nothing wrong with 2 wax rings"

WRONG!!!!!!!!

Not only is the use of two wax rings, or even the double thick wax rings a violation of code, it is at best courting a future disaster.

In my humble opinion anyone who would resort to such mickey mouse methods would do well to confine their activities to cobbling up their own house and refrain from giving advice that at best serves no purpose but to confuse those who are seeking advice on how to do the job correctly.

Thanks for the suggestions everyone. I figured that since a fat wax ring didn't hold the first time, some kinda extension was in order. The home center didn't have any kind of different ones, just about 1/4 thick hard plastic (like the pipe). No kind of seal on it so I figured a little silicone wouldn't hurt.

When i went to clean up the orginal cast flange but some of the pipe was sticking above the flange. It wasn't the cleanest cut (even for cast iron) not sure why it would be like that. Took a grinder and removed the excess pipe and clean up the flange surface. Then a little cleaning and silicone and the two extenders. let the calk dry good and put it all back together.

No leaks yet! Kid keeps clogging it with too much tp.

I am often amazed about how people can speak so strongly about codes when they are so different and in this case almost 2,000 miles away.

What does your local code say about this?

QUOTE:"I am often amazed about how people can speak so strongly about codes when they are so different and in this case almost 2,000 miles away."

In this case it is real easy. Code does not day anything about the use of wax rings, what ALL CODES do say is that we must conform to the standards set forth by the ASTM (American Society of Testing & Materials), ANSI (American National Standards Institute) & ASSE (American Society of Sanitary Engineers). But then if you knew anything about codes you would have already known that.

I live in San Diego. In case anybody is interested. There is no code restricting the use of two wax rings.

The restriction is not in the code, in fact code doesn't even mention a wax ring, however in the general rules of all codes it says all joints must conform to ASTM specifications and ASTM says there shall be no more than 1/4" space between the top of the flange and the bottom mating surface of the bowl.

Thats intersting. In a previuos message you directly indicated it was a "violation of code". I could see why you would follow the 1/4 inch rule. You cant make extra money by adding a second ring. Nuff said.

Instead of trying to find ways to justify substandard work perhaps you should actually attempt to learn something about plumbing before you try giving others advice..

But to enlighten you, Code does not specify how the joint is made, however in the general rules all codes it plainly states that you MUST CONFORM TO ASTM SPECIFICATIONS. Therefore even though the manner of making the joint is spelled out under the ASTM guide lines it is a VIOLATiON OF CODE to make the joint in any other manner.

Now try as you might, there is no way you can justify jury rigged hack jobs as proper, so if you don't know the correct way, perhaps you should refrain from showing off your lack of knowledge.