A toilet I have in my house keeps getting clogged up so one day I ripped up
the floor boards (it is on a second floor) and I followed the toilet 3-inch
toilet drain pipe line. To my dismay, before taking a vertical drop, the
drain runs 15 feet. The drain is well ventilated after about 9 feet and is
at a steady slope of only 1/4 inch per foot. I replaced the drain pipe, but
there was no damage to the original one so I don't think that will help
much. I built a 1.5 inch pedestal below the toilet to slightly increase the
slope. Even though this is at-or-above the 1/4 inch per foot slope minimum,
is this 15 foot horizontal drain setup "up to code"?
Unfortunately, the house is poorly designed and it is pretty much impossible
to move the toilet to a different location. Additionally, there are no
possible different routes for the toilet drain. The closest vertical drain
drop is only about 6 inches away but it is only a 2 inch pipe for the
shower, and 1.5 inch pipe for the bathtub (which merge a couple feet down
the wall). Why didn't the builder run the toilet drain down the same wall?
Who knows... I cannot run the drain line down the same wall myself because
the drains go into a solid block of the concrete below the house.
Secondly, I've been looking at more expensive toilets which may help reduce
the chance of the toilet clogging up in my current setup. My current toilet
it some generic 1.6 GPF toilet. But I am considering a jet,
pressure-assisted, or power-assisted toilet. Kolher advertises their
power-assisted toilet is king when it comes to flushing -- but will this
help me in my situation?
*Thanks* for any input.
There's nothing fundamentally wrong with a long horiz run
at 1/4" per foot.
"The drain is well ventilated after about 9 feet"
What does this mean??
The drain should be vented no more than 3 feet from the
toilet. But I doubt that venting is causing your problems.
Have you determined where the clogging occurs? If you can
plunge it clear, I suspect the clogs are completely within
the toilet .
One of the major causes of clogging in low-flush toilets
is the use of "soft" tissue. This modern stuff wads up
into great clumps which defy flushing. As an experiment,
try switching to old-style tissue for a few weeks.
Yes, you'd probably be happier with the Kohler.
Thanks for your speedy response. The clog is definitely in the horizontal
run because I can take a snake and it doesn't get at the clog for several
feet. If I plunge, I can usually get it unclogged as well but you can hear
all the action in the drain pipe and I lose all water in the toilet (etc).
You are correct, the first vent for the horizontal run is at 9 feet (opposed
to the 3 feet minimum as you said).
Anyway, I am wondering about those power flush toilets because it uses even
less than 1.6 GPF (1.0 or 1.4 GPF) so I am not convinced it will help me.
The pressure toilets look appealing however.
We had a similar problem at work with a 50' horizontal run. It needs a lot
of water so the solids can float away. A pressure toilet helped. One
advantage was that fact that it had a quick recovery. You can flush half way
through your business, again when you are done, again when you use the
paper. That took care of most of the problem.
Fast forward a few years and add a second toilet. Only difference this time
is venting. The first setup was a hack job and not properly vented. The
addition was a good plumber and he added a vent, put in a standard style
toilet and there has not been a problem in a year of use.
One ore thing. Have the ladies dispose of those cotton things in the trash
instead of a flush. The maintenance guy knew when the secretary had her
period by when the line plugged up.
That last tidbit pretty much guarantees that it's a venting issue,
If you've got a solid plug of matter moving down the pipe,
and no way for air to get in behind it, of course it's going
to stop moving.
Since when did they redesign toilet paper? How do you know it is the old
I agree though, replacing the pipe without a firm diagnosis was premature.
A new toilet would have been much easier. Just running a hose down the open
pipe would have shown if it was sufficient to remove the waste.
Regardless of toilet you choose, the diameter of the trap seems to be the
key to troublefree flushing. 2" trap works quite well. You may in fact
have a partial clog in the trap of your present toilet which contributes to
I hope my related story will help you a little bit. It is not about a
toilet but the drain that takes water away from the AC. When I bought
the house it worked fine for a few years, although I didn't use it
much. The drain starts about 5 feet high, comes out just past the
edge of the furnace, down 2 inches, to the left for 18 inches to the
wall, down to the floor and then 8 feet to the sump.
After a few years, when the AC ran water went all over the floor.
After a few weeks of that, I cut the plastic pipe off to flush it out,
ran water through the pipe including all it's turns and it seemed to
come out just as quickly as it went in. No spider webs or anything
came out. Glued it back together but it worked no better.
A few weeks after that, when the water heater was out of the way, I
took the same pipes and rearranged them to go down 2 feet instead of 2
inches before going to the side (to the wall) and then down to the
floor. After that everything worked fine.
I keep meaning to check my townhouse neighbors to see if theirs are
all like mine was, and if they have problems.
I agree. when they talk about good fllushing, they're probably
assuming that your drain is good. But maybe not. Maybe you can reach
the technical department of Kohler or another company by phone. The
advice here is good, but someone who worries about flushing 8 hours a
day every day is going to know more. Check their webpages first so
that when asked you can say that you checked their webpages first.
Maybe they will even have something there.
Remove NOPSAM to email me. Please let
me know if you have posted also.
you may actually prefer more accurate jobsite answers than we can guess
you might have to call a plumber and fix the drain system of your home.
buying a more expensive noisy toilet is not the proper solution.
make sure you have personally inspected the sewer line with mirrors and
flashlights to satisfy your curiosity before you call in a plumber with
a sewer cam you will be at home to watch with the plumber.
but first, with the toilet removed, the floor flange must accept
unlimited amounts of water from your garden hose with no backup,
otherwise professionally have it snaked.
if the line accepts all the water you give it, retest the built-in trap
of the removed toilet by running a closet auger all the way thru it and
pulling a towel back up it to pull out the plastic disposable spoon or
other similar but unsnakeable object somebody dropped in there which is
not presently amusing you. good luck.
There we go! This is most likely the problem's cause. The old codes dealt
with those old 4.5 gallon flushes and not having enough water to wash the
solids away were not a problem, getting the water out and gone was. There is
much debate going on right now that addresses the realities presented by low
water toilets and the codes are s-l-o-w-l-y changing to reflect that
reality. We need less pitch, not more! The idea is to float the buggers out
like a raft, not like a kayak in whitewater. Your run of 15 feet is
problematic because of the low flush. As the poster said: the water is
running out faster than the solids which get left behind and stick wherever
they stop. If you train everyone to triple flush every time they leave a
"package" you would solve the problem. NGH (Not Gonna Happen). You can
Gerry-rig a modern toilet to flush more that 1.6 gallons per flush. That may
be a good solution for you. I've even seen a black market for old 4.5 and 6
gallon beasts around my parts.
While a poor vent can cause drainage problems in certain configurations, the
primary purpose of venting every fixture is to keep the other fixture's
traps from being sucked dry. If you ripped everything out and moved the vent
to the proper location you would probably not see a significant difference.
Most clogs are due to excessive paper use and/or flushing items that
should be thrown in the trash.
The last code I dealt with specified 6 feet as the maximum distance
between the closet flange and the vent. This was for UPC, I believe IPC
allows up to 12 feet. So, I doubt the 9 foot distance to your vent would
be too much of a problem.
If you have room in the joist space, you could add a "Y" in the drain
line to add a vent closer to the toilet that runs horizontally above the
drain line and tie into the regular vent at the other end. Probably not
necessary, but it may be an option if you're worried about it.
I wouldn't go any steeper than the 1/4" per foot slope. The liquids will
rush down the pipe faster, potentially leaving solids behind to cause a
clog. Many of my drain lines are about 1/8" per foot slope, and they
If you had 4" pipe, I would have suggested switching to 3" pipe with a
low-flow toilet. The lower quantity of water can spread out too thin in
the bottom of a 4" pipe to carry away the solids. But, it sounds like you
already have 3" pipe, so that shouldn't be a problem.
Assuming the toilet is the only fixture you are having trouble with, I
suspect the drain is fine. You may want to focus your attention on the
vent. Go up on the roof and check the vents. Run the garden hose down the
vent and/or run a snake through the vent. Sometimes they get clogged with
leaves, birds nests, bee hives, or whatever. Trying to drain a toilet
without a vent is like trying to pour liquid from a can with only one
hole. It'll go "glug-glug" instead of flowing smoothly.
If you live in a cold climate, your roof vent should be at least 3".
Smaller vents can ice over when the moist air leaves the vent, eventually
blocking the vent. If your vent is smaller, you can replace the current
vent with larger pipe and transition to the smaller pipe in the attic
(the closer to the heated space, the better). I'd also install a
"mushroom cap" over the large vent opening to keep out leaves, squirrels,
You may also want to check the float level in the toilet. It may be set
too low and not giving you the full 1.6 gallons with each flush. Or the
flapper may be closing too early, causing the same problem.
We bought inexpensive off-the-shelf American Standard toilets from Lowes
when we built our house 2 years ago. I made sure to pick models with a
large trap diameter, but otherwise we just chose a style we liked. We
haven't had a single clog in the year or so we've lived here, and they
flush better than the 3.5 gallon toilets we had in our last place.
Unless the toilet was one of the first 1.6 gallon models that came out, I
wouldn't worry much about the toilet. If you would feel better replacing
it, I'd just pick up a new toilet, and not worry about all the pressure
assist stuff. They'll just cost more and be a future maintenance issue...
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