PVC toilet flange to fit on the outside of a 3" PVC hub fitting?

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davetrouble

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I am replacing a toilet flange for a 3" PVC hub fitting. I understand that one option is a PVC 3" spigot flange that is designed to fit inside a 3" PVC hub fitting. But it also occurred to me that a PVC 4" spigot flange that is designed to fit inside a 4" PVC hub fitting might also fit on the outside of a 3" PVC hub fitting. That is, as long as the wall thickness of the 3" hub fitting was 1/4". Now, when I measure the wall thickness of the particular 3" hub fitting that I am dealing it does indeed appear to be 1/4". However, I am not able to find anywhere where the wall thickness of a 3" PVC hub is specified to be 1/4" nor can i find anywhere where it is mentioned that a PVC 4" spigot flange will fit on the outside of a 3" PVC hub fitting. So I am wondering if this is a reasonable option or not?
 

Reach4

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I am replacing a toilet flange for a 3" pvc hub fitting. I understand that one option is a pvc 3" spigot flange that is designed to fit inside a 3" pvc hub fitting. But it also occurred to me that a pvc 4" spigot flange that is designed to fit inside a 4" pvc hub fitting might also fit on the outside of a 3" pvc hub fitting. That is, as long as the wall thickness of the 3" hub fitting was 1/4". Now, when i measure the wall thickness of the particular 3" hub fitting that I am dealing it does indeed appear to be 1/4". However, I am not able to find anywhere where the wall thickness of a 3" pvc hub is specified to be 1/4" nor can i find anywhere where it is mentioned that a pvc 4" spigot flange will fit on the outside of a 3" pvc hub fitting. So I am wondering if this is a reasonable option or not?
You have reinvented a common item. That is what the 4x3 pvc glued closet flange is-- can fit over a 3 inch pvc pipe, or inside a 4 inch pvc pipe.
 
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wwhitney

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You have reinvented a common item. That is what the 4x3 PVC glued closet flange is-- can fit over a 3 inch PVC pipe, or inside a 4 inch PVC pipe.
What the OP is describing is different, it would fit inside a 4" hub (a 4" spigot end closet flange) and possibly outside a 3" PVC hub (rather than use a 3" spigot flange inside the 3" hub).

My comments: hubs often have embossed printing on the outside that would interfere with the fit--best case is that you grind them off and then the fit happens to work. But I see no upside--just use a 3" spigot flange. The opening at the bottom of the toilet is smaller than 3" anyway.

Cheers, Wayne
 

Terry

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sioux-chief-inside-3-883-atms-side.jpg


They also make these for PVC. This one is ABS.

sioux-chief-inside-3-883-atms-top.jpg
 
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