I'm getting old...
 

You know, how did I miss the memo that water closet (toilet) drains are now 3" standard... and not 4"...

It seems everyone knows this but me. Am I nuts or have they traditionally always been 4"?

Thanks, Pete

I seem to remember them being 4" when I remodled both my bathrooms........would not doubt it has something to do with flush velocity of the low flush toilets......

First I have heard of this however.

It's that Go&(^*(*&^$%med Bush and the Mo&(^%&^*&*(&^%king Neocons fault.

B

Howdy All,
I'm getting old too. But it has nothing to do with toilet drains :-)

I'm older than you are and I only have encountered 3" drains...........the bottom of the toilet is a 3" opening.

Now, downstream......the pipes typically open up to 4"........but not at the closet, AFAIK.

maybe you are right......My basement is finished (sheetrock) and I have no access to confirm it either way....as I did all this 6 years ago.

The way I understand it is that the P-Trap built into the toilet is only about 2" anyway... so 3" is the "norm" -- All the cast iron in my house going to toilets is 4" as is the main. Go figure. 3" will make it much easier for sending it down walls, I just didn't know...

cast iron is fairly thick...are you measuring outside diameter or inside diameter? In my case I have all copper down to 3 feet above the basement floor where it becomes cast iron.

There ya go. They are 3".

Just replaced the toilet in my master bath, and it had a 4" pipe all the way to the toilet. Barely got the wax seal to fit. Someone wanted it to drain, I guess. The pipe had been replaced sometime, as it's plastic, with the old cast iron pipe still in place a couple feet away(the house was built in 1920).

Yes, I've seen the 4" cast go all the way up to the closets on real old construction...........but.........it's pretty rare. Makes for all kinds of fun to get a toilet flange installed.:o

While we are discussing toilets....
My house was built about 20 years ago, just as the low flow toilets were mandated. The American Standard in the main bath has always been a slow flush. I am thinking of replacing it.
Has fluch technology improved? Without going to a pressure systems, what are the pros and cons of various manufacturers' systems? Is there really any difference?

4" in my house. Old cast iron was 4 and I replaced it with 4" ABS.
There is a difference in efficiency of flushing according to the plumbers at my school. I installed a low flush about 12 yrs ago. It's ok but not spectacular. One problem is that the water in bowl has too small an area so that it needs frequent cleaning.
The only way to test and compare is to line up all the options, drop some large loads and see how each deals with it. I don't know if Consumer Reports has done this.

Bad visual alert !!!

Of course they do it.........they get Shaq as the tester.:D :D