Basic wastewater plumbing

[bluedog225]

It’s been a long road but the septic is finally installed. Now i have water and wastewater.

The plumbing layout is pretty basic. Shower, toilet, and sink with another sink about 20’ away. All of this is on the second level. The main drain line to the septic tank (4”) is on the first floor. About an 11’ drop.

I started writing up a few questions then realized that I need a guide book of some sort. There’s just too many basics that I’m lacking. IPC, UPC, vent sizes, trap arm lengths, etc.

Does anyone have a recommended resource? An overview of my options and how to do this correctly?

Thanks

 

[bb29510]

get you a code check book or the black and decker book on plumbing

 

[The Cobbler]

can you sketch out what your floor plan is, with fixture locations, sewer location, vent location etc?
we might be able to help steer you you thru some of it

 

[mike93lx]

Pitch is really important. Too shallow and you will build clogs, too steep and the liquids will outrun the solids, and you will build clogs.

I agree on getting a book. The rules on the types of wyes always trip me up.

 

[Mr onetwo]

3 basics...1/4" per foot pitch,**** runs downhill and payday is on Friday

 

[mike93lx]

3 basics...1/4" per foot pitch,**** runs downhill and payday is on Friday

Don't bite your fingernails!

 

[Mr onetwo]

Seriously ...reduce your main size within the structure to 3" and increase to 4" at the cleanout before it goes out thru the wall.Do your sink and shower drains in 2" and put a cleanout in under a kitchen sink for grease. Here is a link to 2018 IPC code which I believe you are under.

Digital Codes

ICC Digital Codes is the largest provider of model codes, custom codes and standards used worldwide to construct safe, sustainable, affordable and resilient structures.

codes.iccsafe.org

It is read only but you can screenshot anything for reference.

 

[Mr onetwo]

a floorplan and photos would be nice so we can advise you on these important matters

 

[firebirdparts]

The building is so basic I think the 2 rules of plumbing plus 1/4” a foot plus seeing one example of one sink is enough really.

 

[housewolf]

It’s been a long road but the septic is finally installed. Now i have water and wastewater.

The plumbing layout is pretty basic. Shower, toilet, and sink with another sink about 20’ away. All of this is on the second level. The main drain line to the septic tank (4”) is on the first floor. About an 11’ drop.

I started writing up a few questions then realized that I need a guide book of some sort. There’s just too many basics that I’m lacking. IPC, UPC, vent sizes, trap arm lengths, etc.

Does anyone have a recommended resource? An overview of my options and how to do this correctly?

Thanks

Where are you in TX? Are you installing the plumbing? Will it be inspected? Which code? The UPC Illustrated training manual is a pretty comprehensive source, but expensive. You could check your local library.

 

[bluedog225]

Thanks all. I am near Bastrop Texas. There will be no further inspections. I will draw up a plumbing diagram.

The various types of wyes also trip me up and the vent size if I want a single roof penetration. If I can use 1.5” foot the whole deal, that would help.

Something like the black and decker book may be good. There’s also an online deal called hammerpedia that looks helpful but spendy.

Hammerpedia

Learn How To Plumb a Half-Bath

cf.hammerpedia.com

Stand by.

 

[housewolf]

Thanks all. I am near Bastrop Texas. There will be no further inspections. I will draw up a plumbing diagram.

The various types of wyes also trip me up and the vent size if I want a single roof penetration. If I can use 1.5” foot the whole deal, that would help.

Something like the black and decker book may be good. There’s also an online deal called hammerpedia that looks helpful but spendy.

Hammerpedia

Learn How To Plumb a Half-Bath

cf.hammerpedia.com

Stand by.

I sent you a pm. If there is a toilet on the system, you should have at least a 2” vent. You can (legally) tie quite a few fixture units into a single 2” vent. Probably the whole building.

Fittings with 3 branches include sanitary tees, wyes, and combinations (wye & 1/8 bend). When used as a drain fitting, a sanitary tee can only be used vertically (the branch would be horizontal). With a few exceptions, using wyes and combos is pretty intuitive.

You would not have a problem running 3” pipe at 1/8”/ft. Anything smaller should be 1/4”

 

[dcg9381]

Thanks all. I am near Bastrop Texas. There will be no further inspections. I will draw up a plumbing diagram.

You'll likely need traps too. The venting always trips me up and I have to re-study. This can get a little complicated if you didn't design for it and have floor joists in the way.

Design for clean-outs. I don't know what code is on those, but you'll want them to be accessible.

Take pictures of everything.

The big deal (that I learned) when re-doing a bathroom that was under construction:

Make sure you leak test. Here (not far from you) plumbers insert an inflatable rubber stopper in the "main" and then fill all the upstream drain lines with water. They leave it like that for several days to see if you have any leaks.

 

[Mr onetwo]

You would not have a problem running 3” pipe at 1/8”/ft. Anything smaller should be 1/4”

F*CK NO.....1/4" pitch always, especially with the drop you mentioned

 

[beltfeed]

3 basics...1/4" per foot pitch,**** runs downhill and payday is on Friday

Spot on, you will never get a Golden Corral Commode meal to chug along a drain pipe with an 1/8" per ft pitch !

 

[Joemctag]

You'll likely need traps too. The venting always trips me up and I have to re-study. This can get a little complicated if you didn't design for it and have floor joists in the way.

Design for clean-outs. I don't know what code is on those, but you'll want them to be accessible.

Take pictures of everything.

The big deal (that I learned) when re-doing a bathroom that was under construction:

Make sure you leak test. Here (not far from you) plumbers insert an inflatable rubber stopper in the "main" and then fill all the upstream drain lines with water. They leave it like that for several days to see if you have any leaks.

For me, what makes it complicated is that there a lot of exceptions that ALLOW you to do it a different way than the original standard way. This is where a real plumber can see right away what the easiest way would be.

 

[sjvicker]

Does someone know the definitive answer on slope? I've heard 1/4" per ft is standard and it shouldn't be exceeded but I've also heard that with todays plastic pipes that 1/4" per ft is the minimum and there is no maximum for slope.

I'll be running a pipe this summer that would be about 2"-3" slope per ft if I did a straight shot. I could stair-step the pipe down the hillside and hold the 1/4" per ft but that seems wonky.

 

[T444e]

Does someone know the definitive answer on slope? I've heard 1/4" per ft is standard and it shouldn't be exceeded but I've also heard that with todays plastic pipes that 1/4" per ft is the minimum and there is no maximum for slope.

I'll be running a pipe this summer that would be about 2"-3" slope per ft if I did a straight shot. I could stair-step the pipe down the hillside and hold the 1/4" per ft but that seems wonky.

Regarding pitch, you need to check the plumbing code applicable to your location. Wisconsin allows 1/8" per foot for sanitary drain and waste piping larger than 2".

 

[PCustoms]

Does someone know the definitive answer on slope? I've heard 1/4" per ft is standard and it shouldn't be exceeded but I've also heard that with todays plastic pipes that 1/4" per ft is the minimum and there is no maximum for slope.

Certainly false.

 

[bluedog225]

I believe too much slope pulls the water down and strands the solids. Others will know.

 

[nadogail]

3 basics...1/4" per foot pitch,**** runs downhill and payday is on Friday

You forgot about Never Chew Your Fingernails.

 

[PWC Repair]

This website is very helpful for lots of things.

Plumbing Codes

Plumbing or sanitation codes are a set of rules and regulations imposed by cities, counties or states.

www.engineeringtoolbox.com

 

[Pluribus]

Just watched this last night and thought it was presented well...and succinctly. He also has a video on venting.

 

[Mr onetwo]

I believe too much slope pulls the water down and strands the solids. Others will know.

EXACTLY...on the horizontal main that will be carrying solids 1/4" per foot pitch...no more, no less.I don't care if the code allows 1/8"...that is a minimum ,not a recommendation.I do like steeper pitch on sink and showers because they don't carry solids.Don't put in a garbage disposal unless you want problems.I am old school and always back vent every fixture...no wet vents.Use plenty of hangers to support the pvc pipe so you don't get any sagging.Figure your overall drop at 1/4" per foot from the toilet location (A) to where the main turns down (B). Allow for obstacles and then make the drop under the toilet as deep as possible.

 

[Jim greengo]

Figure out what code you're under 1st.

 

[Mr onetwo]

If you back vent everything properly it doesn't matter....that is in every code and OP stated no inspection

 

[mike93lx]

If you back vent everything properly it doesn't matter....that is in every code and OP stated no inspection

What doesn't matter?

 

[Hakeem]

Does someone know the definitive answer on slope? I've heard 1/4" per ft is standard and it shouldn't be exceeded but I've also heard that with todays plastic pipes that 1/4" per ft is the minimum and there is no maximum for slope.

I'll be running a pipe this summer that would be about 2"-3" slope per ft if I did a straight shot. I could stair-step the pipe down the hillside and hold the 1/4" per ft but that seems wonky.

The pitch was more important with cast iron pipes that weren’t smooth on the inside. Solids would be much more likely to catch on these rough interiors compared with the slick pvc pipes used today.

I don’t have a reference handy but I’ve been told by a few different plumbers that 1/2” pitch per foot to ~45deg is the “no go zone”. After 45deg you’re close enough to vertical to where it wouldn’t matter.

Regarding your case, I’d probably do it as a straight shot with a clean out every 10-20ft. This might be bad advice though, ideally consult w a real plumber

 

[housewolf]

.
Regarding your case, I’d probably do it as a straight shot with a clean out every 10-20ft. This might be bad advice though, ideally consult w a real plumber

I am/was, and I’ve offered to help the OP. I retired after installing, supervising, and/or permitting (on my license) about a billion $$ in plumbing work over 45 years

A cleanout is required where the sewer leaves the building, then every 100’. You seldom run into that on residential but if it’s not required at the kitchen sink, it should be. Also a good idea, and required in some places, to continue the sewer outside the building, if below grade and have an end of line cleanout. Like everything else; good/better/best. What’s “good enough”? The only limit is your wallet.

As far as grade, 1/4” per foot is generally “required” and a good rule of thumb. Much of my work was done on large commercial projects and 1/4” (~2% slope) is often impossible. It’s not unusual at all to have 300’ of pipe from the stub out to the farthest riser, that’s 6’ of grade/elevation change, if the high end has a little dirt over the pipe, the sewer stub out may be below the civil tie in. In my experience, that would be a small(ish) project.

Over the course of my career, I’ve run so much pipe at 1% (1/8”/ft) without issues it pretty much became SOP. Smaller than 3, sometimes 4 if the run is short, is installed at 1/4” if possible but I wouldn’t lose sleep over it at 1/8” in my own home. If it’s underground, it’s almost certainly going to be 1/8” because of the additional excavation, backfill, and compaction, but it depends there too. If I’m tied to a deeper elevation on the low end (having to go under structure), I’ll run more grade (or offset up) to minimize excavation labor.

IME; an even grade is as important if not more than 1/8 vs 1/4” per foot. It’s easier for a laymen to install with even grade if he’s using 1/4” foot. The flatter the pipe, the more skill it takes to install at an even grade, we always use a laser when we’re cutting it close and I’ve had to run pipe quite a bit flatter than 1/8”/ft. There are miles and miles of civil sanitary sewer installed at much less than 1/8”/ft.

 

[nadogail]

When installing drain lines I attached a shim under one end of my level to make the pitch calculation automatic.

All I had to do was keep the bubble on the mark.

 

[mike93lx]

When installing drain lines I attached a shim under one end of my level to make the pitch calculation automatic.

All I had to do was keep the bubble on the mark.

Torpedo levels have marks to show different pitch values

 

[75gmck25]

I installed my plumbing according to code, but looking back on it I would have paid more attention to cleanouts and making them easily accessible.

For example, you can snake a tub drain line through the tub overflow, but if there was a clean out and access panel in the wall behind it, it would take a lot less finesse to run the plumbing snake down through a straight pipe into the drain line.

 

[nadogail]

We often have to learn things the hard way, as we fix our mistakes. I am envious of those who were able to learn from the mistakes of others and avoid making their own.

I have been able to do a little of both styles of learning, but some of my mistakes were costly.

 

[housewolf]

I installed my plumbing according to code, but looking back on it I would have paid more attention to cleanouts and making them easily accessible.

For example, you can snake a tub drain line through the tub overflow, but if there was a clean out and access panel in the wall behind it, it would take a lot less finesse to run the plumbing snake down through a straight pipe into the drain line.

The majority of the time a tub clogs is caused by hair. Going through the overflow plate is probably going to be the easiest way to retrieve hair in a tub drain. Now if you’re trying to push a snake through a p-trap, that’s another story.

Torpedo levels, even without the grade marked are great for short runs of pipe, but if you have a grade you have to hit over a long(ish) run, you’ll be in trouble before you even realize it.

 

[rayra]

Big radius corners / sweeps. Proper downslope.

/The Poop Must Flow.

 

[Mr onetwo]

2 ft level with a 1/2" piece of plywood taped under 1 end and this Redline 5 torpedo level if you can find one

 

[Mr onetwo]

What doesn't matter?

the flavor of code...proper back venting and sanitary piping are in every code.It's the shortcuts that are either allowed or not allowed in the various codes.Up here 2" for kitchen sinks is required above or below ground now, which is a very good improvement to the code.As far as less pitch on gigantic municiple/commercial piping systems with long runs 1/4" pitch is almost always not possible.But not in a simple residential system.You are comparing apples and oranges.