I’m getting ready to do my first bathroom plumbing rough-in. It seems that code allows a 3-inch drain on the toilet, but many of the installations I see (and most of the ABS parts that are available) are 4-inch. Two questions:
– Is a 3-inch drain, in fact, up to code?
– Are there any drawbacks to using a 3-inch drain on a toilet?
Thanks in advance.
Steve Mann
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Replies
1) Yes
2) No
DanT
Thanks very much Dan. By the way, does the "T" in "DanT" stand for terse? That's my favorite type of e-mail message.Regards,
Steve Mann
ABS? Is this a remodel/addition? PVC is the norm now, but if your house already has ABS that's fine. I've made straight connections from ABS to PVC (pipes are the same OD), but code says you should use a rubber band connection.
Depends on your finish flooring...
Many plumbers install a knock-out closet flange. It saves a lot of time in new construction, and has only one drawback: The Height Difference between subfloor and finished floor. ALL closet flanges are designed to "sit" on the finish floor.;IE, they should protrude about 1/4" above the finished floor. If you are using vinyl, you will have about a 3/8" difference due to the vinyl and the underlayment. Tile will have a larger difference.
3 options to compensate:
1) Use a double wax seal. While I know many companies that practice this, the wax can eventually slip and fall into the drain line.
2) Use Ring Extensions. Just glue these on top. Easy as that! Don't raise the ring too high! Test by setting the ring extension inplace (unglued) and setting the bowl (w/ no wax seal) on top. If it rocks because it's too high, don't use the extension. (It may rock a little because the floor/toilet is not level- that's ok.) This method is a long term solution.
3) Shim the closet flange appropriately. You don't have to cut a "donut" shaped shim-- just one under each of the 4 screws. Apply caulk to all the gaps that show the subfloor before setting the bowl if you're paranoid (an ounce of prevention...)
If the floor is tiled, I like to run a 4" up, let the tile man grout flush to my pipe (no gaps), and then set a flange inside. This requires using a pair of Inside Pipe Cutters, a drill bit that has a 1.5" round toothed cutting wheel that fits into standard drills (a corded drill is better, but an 18V may have the power to work). If you use inside cutters, place a wad of something into the pipe. That way if the chuck comes loose, it won't fall into your drainage system. Don't let this tool catch your shoe laces!
DanT is right, a 3" or 4" makes no difference. The trap in the bowl is normally 2 1/8" anyway, so that's your bottleneck.
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Edited 5/25/2005 9:27 pm ET by KakarotMF
"PVC is the norm now,"
No it's not.
how's that for terse?
anyways ... most plumbers think of PVC as "homeowner grade" ... and abs as "pro".
PVC is "glued" ..
ABS is "solvent welded".
Might be the norm in your area ... but "the norm" ... don't mean better. And it's certainly not "the norm" anywhere near here.
Jeff
most plumbers think of PVC as "homeowner grade" ... and abs as "pro".
You are right. PVC here is only code for weeping field and French drains. No PVC allowed inside for years and years now, although I run into it in reno's from time to time. There are adapters available for tying in the thicker-walled ABS to the thin-skinned PVC crap. Also universal solvent glues....
For a toilet hook up, I still use a 4" lead. The type with an abs ring can be solvent-welded directly into an abs waste line. They are available with either 3" or 4" connections.
For floor-height problems, a wax seal with an abs extension integrated into it is sold. This works better than the old trick of stacking two gooey doughnuts.
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Terse? I think direct is the better term. DanT
My in laws are in PGH. I was just their last month. We talk about moving to Washington County eventually...Though I've never done any plumbing outside of NC, PVC is all that is used here for Residential and Light Commercial drain. We still use no hub cast iron for custom home drops and for vents above the drop ceiling on commercial fit-ups if the cheap HVAC guys use that area for a plenum. All the supply houses stock maybe 2 pallets of 3"-10' cast iron, and a pallet of ABS. The rest of the yard is a white ocean of PVC.I commented on the ABS because if the poster's area has switched mainly to PVC (like mine has) then it could be harder for him to find ABS fittings. I just wanted to let him know that PVC would be an acceptable substitute. If having too many options is your worst problem in life, you aren't doing too bad!EDIT: My dad, who learned plumbing w/ good 'ole copper and lead/oakum, told me that back when everything was ABS, any guy w/ a pickup truck could be a plumber because of the "solvent welding" issue. They just quickly measured/cut, then gopped a bunch of solvent welding glue and held it together till it stuck. (What, match up a fitting?) After the switch to PVC (which only uses plain, unworth glue) they couldn't understand why they were having all these leaks...Mark
Plumber
Edited 5/26/2005 8:43 pm ET by KakarotMF
Both ABS cement and PVC cement "solvent weld" the plastic pipe. See Oatey's website.
PVC cement gives me a better Buzz, so if its a weekend we use PVC, during the week (school night & all ) we use ABS.
WOW
Cast is king here, that and copper. We are not allowed to use the plastic pipe... something to do with the noxious fumes that it produces when burned, don't want to kill the firemen. I think that the plumbers union weighed in and had their say but what do I know.
I like cast anyways as it is quiet and with the correct tooling is not that hard to work with.
james
I like cast anyways as it is quiet and with the correct tooling is not that hard to work with.
Yeah, let me just hoist that 30' cast iron soil pipe. No problem, do it with one hand ;)
jt8
It's better to light a candle than to curse the darkness. --Chinese proverb
Yeah, let me just hoist that 30' cast iron soil pipe. No problem, do it with one hand ;)
Well, I generally just lift it 10' at a time but if you want to do the full 30' stack and can do it with one hand you are more than welcome on my crew anytime. :)
james
Buying him lunch might be expensive.LOL
Sorry my man, but pvc and abs are both solvent welded. In the last 30 years, I have not seen anybody use abs [this is Maryland]. No plumbing supply house that I know of even carries it.They gave up on it because of too many problems.
yeah ... right.
Jeff. Buck Construction
Artistry In Carpentry
Pittsburgh Pa
I would be willing to respond if I knew what post we are refering to.
(Sorry, I meant to address this to "all")So, it is okay to mix hubless cast iron (for the vertical drops) and ABS?We are about to start a big remodel which includes 2 second story baths where the drains will run through the kitchen walls. The client is concerned about noise, but I have not yet asked the plumber sub about using cast for the drops, and ABS for the rest. Normally, we just pack the stud cavity with insulation (around the ABS).********************************************************
"I tend to live in the past because most of my life is there."
-- Herb Caen (1916-1997)
Edited 5/28/2005 10:32 am ET by nikkiwood
The ABS and PVC thing is regional. ABS is still a hit in my area but PVC is typically spec'd on commercial jobs. DanT
Around these parts 3 inch is fine for the toilet as long as the main drain from the building to the sewer is 4 inch. Abs is good and it is strong. I pretty much always use it.
Have a good day
Cliffy
Assuming you are using a newer low-flush toilet, a 3" drain is actually preferable. The inside radius of the pipe is tighter than with 4" (obviously!) and therefore a lower volume of water is required to float the solids.
If you haven't bought the toilet yet... get a Toto.
On the west coast, ABS drains are the norm. Once in a while you see some PVC under a house but it's typically what the HO did. I rarely see a plumber with a van full of PVC, although some of 'em like to do quick-and-dirty water supplies in PVC and CPVC.
Regarding the Toto--been there, done that. The drainage is weak. We're going with an American Standard Champion this time. Although, I wouldn't mind a Toto heated toilet seat.Regarding ABS vs. PVC, I've never seen a PVC DWV system here in California. ABS, definitely. PVC for water supply lines, up to the service entrance, but not DWV.Regards,
Steve Mann
Personally, I can... uhhh... create some challenging situations for toilets. Love my Toto Promenade.
Woops. I double checked, and after calling all (6) of the local plumbing supply houses, NONE stock ABS. I guess I mistook the cast for ABS. I asked the guys at the counter, and I was told it went out of vogue in this market 15-18 yrs ago. The only glue that Lowes sells for ABS is labeled "All Purpose Glue for ABS, PVC, & CPVC".The price spread (retail) puts ABS 39% more expensive, according to the Box stores, as they still carry it. I don't know if it's just a "there's no competition" reason. One of the supply house counter guys said that they made PVC in response to the oil embargo, since PVC requires less petroleum to make. I have no idea if that is correct.About one being a Professional product and one being a Homeowner's product, I believe that is obviously false (since it isn't carried by any distributors here). If you need something heavy duty, use cast. Otherwise, plastic is plastic. One is not better than the other, just different. Personally, my crap can't tell the difference.I wonder how the US is divided: PVC vs ABS? Is the Southeast PVC territory? The main brand of PVC around here is "Charlotte Pipe", which is located 3 hrs south.I know better than to start an argument about water lines, LOL. Plumber's tendencies to a certain product (copper, CPVC, Pressure PVC, or PEX) run deep. For the curious, NC mainly use PEX 98% for new residential construction, Copper for most commercial, and occasionally a CPVC job.
Mark