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dishwasher waste piping

jonny88jonny88 Member Posts: 1,139
Good morning all and hope everyone is doing ok out there.A quickie.Dishwasher is been installed in an island about 6ft from kitchen sink.I would like to run a designated waste line,trap and vent.My old buddy the contractor thinks I am overkilling it and he wants to pump it into kitchen sink drain like you normally would if d/s is beside sink.What dio you think?Thanks


  • icesailoricesailor Member Posts: 7,265

    You could also just drill a hole through the floor of the cabinet and floor and drain it under the house. It might not pass an inspection.

    It might be OK in your jurisdiction if the AHJ approves it. If permitted and inspected, hope that the AHJ inspector has a good satisfying meal and no arguments with irate inspectee's before he/she gets to your inspection.
  • RobGRobG Member Posts: 1,850

    This is an interesting one. Are you required by code to have an air gap in your area or can you loop to hose under the sink prior to dumping in the tailpiece or garbage disposer? The next question would be whether the pump on the dishwasher can handle the length of the run (you will have to check the I&O manual or call the manufacturer for that one). My biggest argument against running the hose under floor and to the sink is that someday the dishwasher will have to be replaced and some poor schmuck will have to get a new hose over to the sink (or rig up the old one). In my opinion even if it IS legal to run the hose under the floor I would still run a drain line with a vent (either a bow vent or a line vent).


  • j a_2j a_2 Member Posts: 1,796

    Just drain the conventional way,,,,keep it simple…..If in Mass keep it legal, recent house I was doing heat system,decided to do kit,and 2 baths on there own….Beautiful job, BUT they had to do it twice, build. insp made them rip it out…..NO PERMITS…
  • jonny88jonny88 Member Posts: 1,139
    permits on job

    Not looking for a shortcut.D/S waste is 6ft i believe from kitchen sink cabinet.I dont want to run hose all that way.I dont like short cuts and want to do right way but this bloody GC is held up on structural issues and now just wants everything done bing bang boom.Dont work like that though
  • icesailoricesailor Member Posts: 7,265
    Indirect Dishwashers:

    Non-Commercial/residential wastes are Indirect Wastes. The waste needs the heights to the top of the drain hose under the cabinet, to give it back pressure so that all the water isn't drained out of the tub on machines that don't have drain solenoids. Not all machines have drain solenoids. But they all have indirect drains. The sink beside the dishwasher provides the indirect drain. The places where code requirements require the air gap device above the counter top is to make the indirect drain above the flood level rim of the fixture (sink). But the sink becomes the receptor. If you want to put the dishwasher into a separate, unconnected cabinet, that cabinet should have a properly trapped and vented indirect waste receptor in it for the dishwasher to drain into. The drain level from the sing drain entrance (DW Drain tee or disposal connection) to the top of the loop allows the water to drain out but leaves the hose full of water. If the disposal or sink fills because of a blocked sink, the air will cause a air lock and prevent the sink waste water from draining back. If it doesn't, work, the entire contents of the sink and disposal will back up into the dishwasher and overflow.

    There are often unresolvable issues with that type of drain. If it is a dishwasher without a drain solenoid, the excess water can back up into the dishwasher tub, and because of the timer control limitations on drain cycle times, the dishwasher doesn't completely drain.

    Its always difficult when these so called "GC" Experts, put their self inflicted problems on everyone else. Then they want you to help solve their financial losses at your expense. When YOU didn't make the "structural issues" mistakes. If they (GC's) spent less time on being experts in our trades and focused that time on being experts in their own trade, things could run a lot smoother.  
  • SWEISWEI Member Posts: 7,356
    Trade Experts

    seem to be getting hard to find these days.  I don't think we have a truly competent plumber younger than 55 in these parts, and the pipeline is not filling up from what I can see.
  • j a_2j a_2 Member Posts: 1,796

    I was a half time plumbing/heating teacher at a local high school…Got laid off, and never asked to return….Why, because not enough kids had an interest in the program…Even the full time teacher went to half time…But I can say, the ones that stuck with it are doing great….
  • jonny88jonny88 Member Posts: 1,139

    thanks and your recomendation is duly noted and will be piped accordingly

    Swei ,I worked in NYC for many years and believe me we covered a lot and most I learned from old timers.I recently moved to where city codes followed and town by town you have different inspectors asking for different things.Yes Swei,I have worked on 8inch sewer pipe in a 50 story building and yes everyone was home and saved their last flush for us.Yes I have worked on 4Inch threaded gas.I have been around a little bit .I amtrying to get to grips with studor vents, wet venting all the things we never did.Sorry if my ? offended you.Yes I can do a lead wipe and yes I hate pvc and pex .As I recall pex should only be run using a homerun system how many times do you see that.I have the greatest respect for old timers and when icesailor speaks i listen.Thanks.
  • SWEISWEI Member Posts: 7,356
    No offense taken

    and none implied -- especially towards you and the others here we see who clearly have an interest in bettering both their work and their profession.

    The majority of big cities still have unions -- and most of those at least make some kind of effort towards training their people.  I have learned over the past decade that small town America is quite a different world.  Median income here is under $30k.  On $40k you a can own an house and live something resembling a life, yet we have trouble filling $50-60k jobs in quite a few fields.  Truly a strange world.
  • jonny88jonny88 Member Posts: 1,139
    thanks swei

    I was venting.Sometimes in these local towns the inspector comes with his hand out first.Ii appreciate all you contribute here and that is why I am here,as it can be said you as good as the person who trains you so there is always room for improvement.Problem I am having is I get all these licenses for different towns,but a lot of GC's dont pull permits which in turn means they do their own plumbing.Poor old Mrs Jones has no idea what is happening to her but is being sold a good story.Again I apologize if I came off a bit crude.Thanks for your response.
  • icesailoricesailor Member Posts: 7,265
    Unions. Codes & Learning:

    In some ways, the Unions have contributed to the problem of a lack of new blood.

    In Massachusetts, we have a comprehensive uniform plumbing code 248 CMR. In 1965, the code covered the entire Commonwealth but only for towns that were over 10,000 in population. Towns smaller could do whatever they wanted. Boston had their own code. If you lived and worked in Worcester, MA and you wanted to work in Boston, you needed a Boston license. In 1965, they started lowering the population requirement for small towns that were covered. The town I worked and lived in was still under the limit, but everyone decided to get licensed. We all still had to take tests There was no "Grandfathering". Some old "Grandfathers" wouldn't take the test and quit working. Those of us, the rest, hired someone to teach us what was asked on the test. "Test Teachers". Ours was an instructor at a Vocational Trade Technical High School. It was stupid money. In my group where I came from, I was the only one who passed. We all passed the written test, they all flunked the practical test because you had to silver braze a copper fitting and the instructor hadn't shown anyone how to do it. He didn't expect that on the test. But having spent 6 years in the LA City School System taking Industrial Arts/Vocational classes, I was well practiced in the art of brass brazing. I convinced the test person to "just let me light the torch". When I cracked the O2 to give the gas a sniff of O2 before I lit it off, to avoid the "Black Floaters", he knew I knew what I was doing. So much for that.

    The Board of Examiners noted that most all the apprentices that had done test prep schooling, passed the written part of the test. So they made it a requirement to have 100 hours of applied schooling. The pass rate went up to well over 90%. It wasn't a requirement, but in 1974 when I went for my Master's license, I did another 100 hours. Time and money well spent. You can never learn enough. I passed first try. At some point, 248 CMR changed to cover the whole entire Commonwealth. No matter where you worked, 248 CMR was the code and that is what you went by. Cities and Towns couldn't have their own Codes. Four year "Voke Students" could graduate from Voke Schools with the 100 Hours of applied schooling. They got 1 1/2 Years credit on the three year work requirement, and if they had worked hard and worked after school and Summers, a really ambitious student could get his Journeyman's Plumbing License after graduation from high school. They, the Board changed the Educational Requirements to 300 Hours and three years apprenticeship. Your apprenticeship can only be done while legally employed by a Licensed Master Plumber who must swear under perjury that they have tax records for the employment of the apprentice. Cash under the table doesn't cover it.

    The Pass Rate was overwhelming. But when the educational hours were changed to 300, instructors complained that they had a hard enough time coming up with things to teach for 100 hours, what were they going to do with 300 hours. I can't recall any apprentice that worked three years and did 300 hours of schooling that didn't pass on first try. They were all code and theory weenies.

    Enter the Unions. They have a 5 year apprentice program that you need a multi generational legacy requirement to get in to. They lobbied hard to get the apprenticeship and educational times to coincide with theirs. Which happened. I said that there would be problems. There have been. Now, a graduate of a Voke School, doesn't have enough classroom training to qualify no matter what. And they need some amount of years of apprenticeship to add to what they get from the Voke Schools.

    What I'm trying to point out is that you get some bright 18 year old, who now faces 5 years of apprenticeship/employment with a licensed Master Plumber and 500 hours of applied schooling, at low wages and probably not being able to be continuously employed for 5 years. What I saw was an immediate drop on new Apprentices. They can't imagine spending 5 years doing something they might not like. If they do go through all this training to get licensed, they work a year and leave to start their own one man business. In Massachusetts, you need a Master Plumbers License to hire another Journeyman and Apprentice. Laborers are considered apprentices if they pick up a shovel to dig a trench.

    Now, we need 6 hours of CEU every year to keep your license. 3 hours on gas and three hours on Plumbing. They have a hard time coming up with curriculum for each 6 hour CEU. Everyone is smarter and better educated. The "Board" sets the curriculum. Inspectors now need to be licensed and they have their own special training. Their CEU's are for 12 hours per year. So that they are all on the same page. The real problem is that the requirement to get licenses is so long now, that it discourages new people from going into mechanical trades. They just put in a Sheet Metal License. Next, it will be expanded to residential wet heating. Or a pipe fitters license will be lowered to cover boilers under 400,000 BTU's.

    Homeowners go to Home Depot or Lowes, buy what they want and install it themselves. And make a mess. Watch those DIY reality shows with kitchen remodels. Are you shipping me? Those homeowner couples aren't doing those kitchen Reno's like they appear. They have (behind the scene) professional help. I probably know more about those kind of things that the "professionals" that they have helping. Ripping out bearing walls to have an "Open Design" is a lot more complicated than they show, And there's a lot more to putting up a couple of temporary walls on either side of a bearing wall you want to remove and put a big long LVL beam under the load. No mention of the fact that you might need an engineer to design and stamp it, and you might need a column to shorten the span and a pier under to pick up the point load.  And the DIY'er who doesn't get Permits and inspections will do a fine job.

    When I was 19 years old, I started plumbing because we were all laid off from a big Union Carpenter Job when I was a union Carpenter Apprentice because they didn't want carpenters banging on walls while they were plastering. I got a job as the second person hired by my old dead boss. If I knew I would have faced 5 years of apprenticeship and 500 hours of schooling (100 hours per year) when being paid apprentice wages with three children by the time I was done, I'd still be a carpenter. Massachusetts Voke Schools are filled with a waiting list to get in. They graduate some of the best mechanics.

    Education is a wonderful thing. Too much required can be a bad thing. One other thing about the Voke Schools, they are often a dumping ground for the students with mechanical attitudes but poor academic skills. Voke Schools teach you HOW to learn. And what you NEED to learn. With the National "Teach To The Test" craze, Voke Schools often count in the overall academic average. School boards hate adding Voke School scores into their averages.

    But the best mechanics come from the Voke Trade Schools.

    Sorry for my long rant.
  • SWEISWEI Member Posts: 7,356
    Nicely put

    and I see most of the same issues here in NM.  Many Towns (ours included ) have our own building departments and inspectors, but only the big cities can afford their own M&E inspectors.  This can sometimes land us in jurisdictional p!ss!ng matches.  Separate codes for every town?  Yikes - reminds me too much of Texas.  Our educational issues tend towards the under-clueful, but we have a similar chicken-and-egg issue with experience.  8,000 documented, notarized affidavit-supported hours of working for a licensed contractor.  Very hard to accrue those on commercial jobs living in a town of 10,000 located 3-5 hours away from major population centers.  Once they leave town to get the hours, they rarely return.

    I worked an IBEW job for a bit back in the mid-'80s.  Never got another day of work out of them.  My dad was (still is, actually) a tax accountant and I had no known legacy.   I gave back in dues roughly the same amount I had earned, then gave up.

    We (as a society and as professionals) need to fix this.  Might be soon.
  • icesailoricesailor Member Posts: 7,265

    Statewide uniform codes equally applied and enforced are the solution.

    Massachusetts may have some issues, but one registration is the solution. A local jurisdiction can apply a local rule that is stronger with cause. You can't outlaw PVC because some prehistoric inspector says "I just like to see that nice cast iron soil pipes with caulked lead and oakum. There's just nothing better". Hog Wash doesn't wash. We even have a Statewide plumbing permit that is code required. A town may put other things on another side. A town can't refuse a application that meets the State standard but not the town form. The town has to make their form comply

    A bigger problem is the competing codes. They all want to sell code books. There's a lot of cash in printing and selling code books.
  • SWEISWEI Member Posts: 7,356
    Competing Codes

    NM pairs the UMC/UPC with the IBC/IFC.  Every three years, the electrical and mechanical bureaus have to crawl through all of it and amend the NM codes, which the legislature then has to pass.  Then the guys in the field get to find the things they missed, and argue over them with inspectors.  Roughly $500 per cycle to stay current on the books alone.
  • icesailoricesailor Member Posts: 7,265

    Again, we don't have to go through that BS. We follow some of those codes described, but it is up to The Board to wade through the BS and come up with a "Unified Code" that has one reference book. Because of certain "difficulties", we are still working off the same code book from 2005.

    Then, with all the CEU required, and the fact that the Board sets the curriculum on what they want everyone to focus on, every one stays on the same pages. It stops that BS where certain inspectors get the big head and want everyone to do things "The way I like".

    No one in the State of New Mexico will want to give up any control to the State. They'll want to keep it local. So they can hassle the competition away. Save it for the "locals". It doesn't stop DIY'ers though, or the unlicensed ones that help them.

    That State to your East must really be a yellow rose. County Codes for each county and little if any continuity.

    All those Right To Work For Less States are real peach's.

    Especially ones that let the employers designate the Plumbers.
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