For my addition/remodel project, I will have a master bathroom (toliet and shower, sink) about 64 feet from my main sewar trunk line that runs next to my house and feeds the sewar in the street. So, somewhere I read that the slope of a drain line should drop 1/4 inch for every foot of run, meaning I would need the toliet and shower drains 4 feet higher than the point where it connects to the sewar line. The drain is literally on the other side of the property where all the kitchen and bathrooms are now. The main drain is about 4 feet under ground, it’s cast iron then connects to the red clay pipe
that lets the roots in.
So, I have enough drop to meet the rise/run requirement since will have raised foundation for the addition, getting four feet should not be an issue especialy since the drain is 4 feet down, but is having this drain be 64 ft long asking for drain problems ? Am I forced to use those noisy pressure assisted toilet ?
Should I add some in line pump to move the waste ? Or not worry about it and go buy good beer instead?.
Replies
Not being a plumber, I'll hold back my own version of the truth here to avoid looking too goofy,there being a variety of opinions on long runs and pitch of pipe but I am wondering - do you not plan to use a licensed plumber for this? He would know.
And if not using one, will the city let you do this without?
They will certainly require a plumbing inspection regardless, and that inspector is the best person to ask for this answer
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thanks for the reply, trying to not used a plumber to keep costs down and frankly the plumbing for my new kitchen and addition will be pretty simple for me and yes city will approve all of the work.
Done all the time
You should not have any problems running a sewer line 64ft. with 1/4in. pitch, some sewers are run with a lot less pitch (engineered) for miles. You never want to use a pump unless you have to, mother nature (gravity) works best.
If you have terra-cotta pipe that is getting roots into it you should think about replacing, it's going to keep happening.
64ft @ 1/4 inch per foot = 1 inch for every 4 feet of run = 64 /4 = 16 INCHES of drop needed over 64 feet.
Simple
Yeah, 16" is correct for minimum pitch, but think how fast it will drain with 48"!!
Should help alleviate any concerns.
JimNever underestimate the value of a sharp pencil or good light.
Some claim that too much pitch can be bad, but I don't know what the parameters of that might be.
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
?????
What about those pesky vertical pipe runs from the 2nd floor to the first?
Heard about too big pipe size for flow rates which decrease "self scouring", but never heard about too much pitch. Didn't think that was possible.....
JimNever underestimate the value of a sharp pencil or good light.
Just what I've read. Theory is that the water runs off so quickly that solids are left "stranded".
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
Ahh, so something greater than 1/4" / ft but less than vertical -- pretty wide range.
Have to look into that, have seen seemingly problem-free drains run at 45 degrees (12" / ft) but usually only for short distances - 6 feet or so.
JimNever underestimate the value of a sharp pencil or good light.
Yeah, I have no idea how "real" the problem is. We have a 45-degree drain running from our kitchen sink, and it's never in 33 years given us trouble (save for the one time it froze up).
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
How the heck did it do that?
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Happened over 30 years ago, the first winter or two after we bought the house. It was incredibly cold (35 below, which is cold even for here) and I suspect that the builder-installed insulation wasn't very tightly installed in the utility room (right below the sink), though I don't really recall what the scenario might have been.
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
So the trap froze? That I can understand.
Yeah, those -35º nights get chilly. Does that fairly regularly up here in late December and through January. Had a client's main waste line to the septic tank freeze up one year; got the call on a Friday night about 11pm, right after the renters arrived from the city for the weekend.
I dug out the septic tank cover and popped it, saw the tank wasn't frozen but hit a blockage about eight feet back towards the house with my snake. Hell and damnation. All this at midnight at about -40º and I gotta go to work on the Mountain at 6am.
The chalet is only two doors down the road from me; I told the renters (nice young family with a couple of kids), "Look; come on over here and take showers or whatever you want; I'll leave the back door open for you tomorrow while I'm at work, and I'll get a guy over here with a steamer as soon as possible."
That's what it was; over the years a 4" dip had formed in the middle of the drain line caused by ground settling where the driveway ran over it. Created a mini 'trap'...and it froze.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
No, I don't think it was the trap, I think it was the diagonal pipe against the outside wall in the utility room.But it's been so long (and I was such a HO novice at the time), I can't say for sure.
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
Hard to see how a 45º-sloped drain pipe could retain enough water in it to freeze. The pipe I described that froze was only pitched the standard quarter or half inch per foot, and ran horizontally under a driveway that was, of course, plowed clear of insulating snow in the winter.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
I vaguely recall that the sink was left full of water overnight, and presumably the slow drip-drip of water through the slightly leaky sink stopper did the deed. But like I said it's been over 30 years.
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
"Hard to see how a 45º-sloped drain pipe could retain enough water in it to freeze."
You can have a vertical pipe freeze and bust if it has a slow continous leak and the temperature is cold enough, it dosen't contain a lot of water, but the ice keeps building up until it freezes or cracks the pipe, replaced many outside sewer risers over the years, just info.
"If all else fails, read the directions"
Thats why the plumbing in high rises has velocity breaks built into the risers, don't ask me how to figure them, that is done by the engineer, just info.
"If all else fails, read the directions"
I can understand the need for velocity breaks in a high rise - don't have any clue as to how to figure them.....
DanH mentioned that too much pitch might be a problem in some situations by causing liquids to drain too quickly leaving "solids" aground in the pipe.
!/4"/foot being more or less standard minimum pitch for sanitary drains in residential housing.
Ever hear of too much pitch being a problem? I always thought there was not any problem with "too much" pitch, but always a potential or latent problem with too little.
DanH couldn't recall what was "too much", any opinion or info? I brought up the vertical pipes which obviously would not tend to leave any stranded solids and also the 45* relatively short run drains I have seen in various homes.
Not a plumber (obviously), but I stayed at a Holiday Inn Express once.......
Jim
Never underestimate the value of a sharp pencil or good light.
Edited 10/11/2009 3:57 pm ET by JTC1
1/4" for 3" and under is minimum. More is better. Code writers are looking at wether or not 4" mains are too large for low flow fixtures.
>>Code writers are looking at wether or not 4" mains are too large for low flow fixtures. <<
I have heard of that concern -- insufficient flow for "scouring".
That being said, I will tell a shaggy dog story about a 4" drain and a low flow fixture.
Shaggy dog story begins here:
I was the house leader working on a HfH house which had a female site supervisor. The SS could not handle using the PortaJohn like the rest of us. She had the plumbers (pro, subs) "temporarily" install a toilet in the first floor powder room.
Some Tyvek tacked over the widow served as a curtain, and a few sheets of luan as walls, hung an interior door and voila - a functional powder room for the females only. Roll of TP, a bottle of waterless hand sanitizer, roll of paper towels and a drywall bucket completed the "facilities".
One Saturday afternoon, the female soon-to-be-HO used the powder room ---- and managed to flush her keys along with other unknowns down the toilet.
The powder room was located at the back corner of the first floor, the sewer line out of the house was diagonally across the house at the front. Path of 4" drain was straight down ~1 foot, then 36' to front of house then 90* across the front for 18' then 90* straight down again for 3' or so, under the footer, then out to the street. All in house piping pitched ~ 1/4"/ft.
Clean outs were located at a Tee under the toilet and again in the vertical drop just before the drain line entered the concrete mud slab in the crawlspace to go under the footing.
The SS came to me and told me what had happened. I discretely asked whether this flush involved #1 or #2. She told me #1.......OK said I (at least it was after lunch).
I rounded up a flashlight and a pair of channel locks. Opened the clean out plug under the toilet and peered into the pipe -- nothing, but I could not see around the 90* at the front of the house.
I told the SS that they were gone u-n-l-e-s-s they were in the 18' run across the front of the house...
I opened the clean out at the vertical run just before the slab, and poked my hand in as a "screen", SS flushed again and the keys promptly landed in my hand.
I emerged victorious from the crawlspace with the still-wet keys in my still-wet hand. 3 keys and a keyless car entry thingy on the ring.
To my utter amazement the HO said, "Oh, ick, I can't use those --- they've been in the toilet!". WTF? I said incredulously, "You have 2 kids? How the hell did you ever change a diaper? You need to grow up and soon!" She never spoke to me again even though I was on site many more times while her house was being completed.
The point is that those keys made it 36' plus on a single flush from a 1.6 gallon toilet and I am sure they didn't travel through the toilet gooseneck or "flow" as well as most "solids" which are traditionally flushed. I know that no additional water was run after the flush since there was no other water source in the whole house.
But, I don't know how far they would have gone in a 3" pipe either.....maybe around the bend and out of the house......
Jim Never underestimate the value of a sharp pencil or good light.
I'm not a plumber either so this is going to be a little sketchy and I don't know the specifics....
Here, when running the sewer line from the house to the municipal sewer at the street on new construction if a drop of much greater than 1/4" per foot is needed the line will get a steep downslope using 2 45s. See attached pics.
On an apartment job I was managing the utility contractor's surveyor made a mistake and misplaced a manhole. This caused the outlet pipe run to be a little less steep than had been specked by the engineer, and and the inlet was steeper than speced. After a project is built, an "as built" survey is done so that the engineer can certify that the project was built according to design and this certification must be submitted to the city for approval. Well it was bad news.... If memory serves, the sewage pipes had to be >= to 5% and <= 10%. (I am sure about the 10% part). Yes - for municipal sewer they go by %, not 1/4" per foot, etc. I'm sure one of the math whiz guys here can translate it for us. I probably could if I felt like thinking about it.... Anyway it was determined than the outlet pipe run of the misplaced man hole would work OK, but the inlet pipe run was too steep. The fix was to build another man hole upstream, to break it into 2 pipe runs with acceptable slopes. Attached is a quick sketch. This fix wasn't a arbitrary thing... there were lawyers and engineers involved...
In case anyone reading this doesn't know a man hole serves a few purposes.
1) (the most obvious) it allows access to sewage line for the purpose of cleaning them.2) it allows grade changes >10% to be dealt with.3) it allows changes in direction of the line and allows junctions of multiple lines.4) it allows an overflow point (other than people's houses) if a sewer main gets blocked.
Edited 10/11/2009 6:10 pm ET by Matt
Thanks!
Now I seem to be getting somewhere closer to an answer.
Slope between 5% and 10%.
Now if I can figure out what that is in inches per foot, I'll have it!
JimNever underestimate the value of a sharp pencil or good light.
I'm not sure about the 5% part. The 10% part I am sure about because this is the city spec that was exceeded and was the big prob.
I *think* 1/4" per foot is about 2% as that is what city sidewalk cross slope is supposed to be.
5% of a foot is 1/20th of a foot, or 12/20 inches, or 96/20 8ths of an inch. 96/20 is close enough to 100/20, or 5/8" per foot. 10% would be about twice that -- about 1 1/4".Going the other way, 1/4" per foot is 1/48 foot, or about 2.1%.
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
I've seen this logic/mistake made. With this scenario, the fluids flow fast and the solids stick. Not a chore I want.
I don't think distance is an issue. It's gravity and it doesn't care.
Size of the pipe?
Could you run the 64' line past the fixtures and have a cleanout upstream on the outside?
Just in case?
The clay pipes are the weak point. I had those once and replaced them.
Will Rogers
Edited 10/10/2009 4:38 pm by popawheelie
Sometimes the inspectors will allow 1/8"/ft in situations like yours. Might want to check with the building department.
Your fine with the right amt of fall.
Just add a couple of cleanouts along the way.
Standard Tees work well because you can run the snake< if ever needed, either way.
Standard tees.....snake 2 ways.....
That's good advice there!
JimNever underestimate the value of a sharp pencil or good light.
Code here is, any pipe 2" or less needs 1/4" fall per Ft.
Larger pipe doesn't require as much fall.
4" can be run at 1/8" fall per Ft., so 64' would use about 8".
64' at 2% would be 1.28'
64' with 15 inches of fall would work just fine.
McPlumb,
This discussion started with an error in the OP's calculated fall for a 64' drain line which was pointed out around ####.7.
OP had calculated 64' as requiring 1/4"/ft fall and came up with 48" fall. It was pointed out that 64 x .25" was 16", not his erroneously calculated 48".
I commented that 48" was considerably greater than 16", so the drain should work fine, based on my assumption that more would be better. 48" = 3/4"/ft.; well above the minimum required.
####.8 or so, DanH mentioned that he had heard that too much fall could be bad for drain performance, as perhaps the liquids would run off too fast, leaving solids stranded in the pipe. He only had a vague recollection of this and could not assign a number to "too much".
Most of this discussion has centered around the question of "Is there such a thing as "too much" fall in a residential drain of this type." And if so, how much is "too much"?
Opinion?
One municipality's sewer lateral specs (pitch >5% and <10%; >5/8"/ft, <1-1/4"/ft) and high rises (velocity breaks) have already been discussed.
JimNever underestimate the value of a sharp pencil or good light.
This discussion started with an error in the OP's calculated fall for a 64' drain line which was pointed out around ####.7.
That is correct, but if you read the OP, it comes out that they realize they have enough fall, but the major concern it the length of pipe. Which has been answered, given the correct diameter and fall, length is of no concern
Since when do we terminate a thread once the original question's been answered? (In fact, isn't it a violation of BT's unwritten rules to actually answer the question in the first place?)
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
>>....given the correct diameter and fall......<<
Correct you are and minimum falls have been well discussed, but DanH raised the topic of "too much" fall.
This concern was again brought up in the municipal sewer post in which rework on a project was required to correct excessive fall (at least by their specs).
The municipal enginering departments spec dictated a minimum and a maximum fall. This may have been the result of an over zealous engineer, or there may be some other good reason for specing a maximum fall. That's what I am trying to determine - maximum fall in a residential drain for long-term, trouble-free performance. Does it exist?
Incidently, both municipal specs are well in excess of the 1/4"/ ft minimum (or 1/8"/ft minimum for pipe 3" and over) discussed here. 5/8"/ft to 1-1/4"/ft = municipality's acceptable range.
And DanH is right - where is it written that we end a discussion at BT just because the original question has been answered....assuming we answer it at all!.......mighta' missed that memo.... ;^)
Jim Never underestimate the value of a sharp pencil or good light.
Keep in mind that I said I wasn't sure about the minimum 5%.
BTW - above I posted a few photograph of a house sewer being installed. When the plumber was there I asked him (an old-timer) about the too much slope thing and the poop being left behind by the water. He confirmed and said that was why he did it with the 45 degree section. I'm guessing this might come under the heading of good practice, even though there is apparently not a code to enforce it.
Also BTW here is a pic.
Your illustration provides more info than any other offered.
Quantifies 1/4" to 1/2" per foot produces the desired drainage results.
Thanks.
Jim
Never underestimate the value of a sharp pencil or good light.
"given the correct diameter and fall, length is of no concern"
Have we yet decided on how many clean outs are required? The code here specifies one where the pipe exits the building and then at a maximum of 40 ft.
And yes I agree with DanH. It is considered bad form to actually answer the OP's question here at BT.
Edited 10/12/2009 10:08 pm ET by fingersandtoes
I agree that it's possible to have to much fall.
Trouble is, I don't have any numbers to verify this.
It also occurs to me that the too much fall numbers may vary with the type of pipe used.
Castiron is rougher on the interior surface than PVC, and probably would produce different results.
Not much help, am I?
Not really much help, but thanks anyway!
This may remain one of the great mysteries......
JimNever underestimate the value of a sharp pencil or good light.