4" flange not compatible with 3x4 closet bend?

[Maine Way]

Hello All,

What is the deal with toilet flanges and closet bends? It seems like 3x4 closet bend is typical to reduce 4" flange to 3" pipe, but the flanges I have found reduce 4" to 3" from the flange to the drain connection. I have mis-ordered twice now a 4" flange to match an order of 3x4 closet bends, assuming the 4" flange would fit the 4" end of the bend. Should I just order 3x3 elbows instead of closet bends? Are they elbows essentially the same as closet bends? Are 3x4 closet bends meant only to join to a 4" drain, since closet flanges all reduce to 3" anyway?

Lastly, do most toilets work with 3" or 4" flanges, or modern toilets are typically 3"?

Shawn

 

[Terry]

The outlet of most new toilets are about 2" dropping into a 3" pipe, most of the time.
When I have used a 4x3 closet bend, the 4" side is for the 4" hub flange and the 3" side goes downhill from there.
I have mainly used the 4x3 closet flanges for 3" pipe and fittings. If I'm dropping down a ways, a 4x3 hub flange, dropping further down to a 3" 90.
You can also used a spigot 4x3 into a 3" 90. It depends on your layout and the distance between fittings that you're working with.

A typical 4x3 closet bend that would take a 4" hub closet flange.

 

[Sponsor]

 

[Reach4]

I have mis-ordered twice now a 4" flange to match an order of 3x4 closet bends, assuming the 4" flange would fit the 4" end of the bend.

Should have fit. If you get an outside flange, you need clearance around the bend input.

There are some nice no-glue compression flanges. Some fit outside, and some fit inside. No-glue allows do-overs. If you glue, make sure you get it right the first time.

 

[wwhitney]

Not sure I follow the question.

Plastic flanges are available with 3" or 4" hubs, 3" or 4" spigots, or 3" or 4" inside fit. [Some are more than one, e.g. 3" hub or 4" inside fit.] A plastic 3" x 4" closet bend is available as hub x hub or hub x spigot, i.e. the 4" end is a hub or a spigot.

So a spigot end 3x4 closet bend should fit into a 4" hub closet flange. Or a 4" spigot closet flange should fit into a hub end 3x4 closet bend. If both are hub end, you'll need some pipe in between. And if both are spigot end, you'll need a coupler.

Cheers, Wayne

 

[Maine Way]

Thank you all for the guidance. I will update with photos on Thursday to show the mismatch between fittings. The 4" flanges I have are meant to connect to 3" pipe only. So they are not designed to slide into the 4" hub of a 4x3 (double-hub) bend. It seems like a poor design.

As Reach4 suggest, a non-glue compression flange may be a good options. I have ordered 4 bends and 8 flanges (4 each of 2 types) and no combination is compatible. So, I am left to decide what parts to ship back and pay shipping. I had thought it was strait-forward, so I was confident in the order...

The two toilets I am using on the project are from different manufacturers and the specifications I could find read:

Toilet type one: 3.5" outlet size
Toilet type two: 2" trapway and 2" flush valve

I am assuming that if I use a 4" flange, any toilet can work. Wax gaskets come in one size, and the hole spacing for bolts is always 6", so it will make a seal and work well regardless? Or is there any advantage to a 3" flange? There must be a reason they make them.

This forum is becoming an important resource for my project and all the input has been helpful.

Shawn

 

[Reach4]

Thank you all for the guidance. I will update with photos on Thursday to show the mismatch between fittings. The 4" flanges I have are meant to connect to 3" pipe only. So they are not designed to slide into the 4" hub of a 4x3 (double-hub) bend. It seems like a poor design.

4x3 closet bends /closet elbows come at least a couple ways. I would usually opt for the one with a pipe-sized (spigot) input.

Those can take an inside or outside 4 inch closet flange, because the part that sticks up is the same size as a 4 inch pipe. A common 3x4 (3" Hub / Inside 4" ) flange can glue inside of a 4 inch pipe or outside of a 3 inch pipe, so that could go in the input of one of those We would call that a spigot or street closet bend or closet elbow, which usually have a hub on the 3 inch output.

There are also closet flanges that have a hub input. Those would only accept a spigot 4 inch closet flange or a piece of 4 inch pipe to extend up to a closet flange up higher.

So those would usually have a hub on both ports.

 

[Maine Way]

Super helpful Reah4! I think this has solved my issue by demystifying the closet bend...