How easy is it to replace my kitchen sink pipes?

Are they certain size? I have seen the white and black PVC. I also have a vent pipe the over flows under the sink. There are two vent pipes on the roof so why would there be a short one under the sink?
  9 answers
  • 1240839 1240839 on Dec 01, 2017

    Black pvc is for drainage/sewer. White, cold water. Off white, hot water.

    sewer vents go up and out, the short one is an air gap.

  • Ken Ken on Dec 01, 2017

    I'll start with the short one. There may be two vent pipes in the roof but none is over this sink. Cannot see it in the picture but there is an Air Admittance Valve on top of that short stack. Lets air in and not out to make the drain flow properly.


    Kitchen drains are 1-1/2". Bath drains are 1-1/4". You will find a kit at the hardware store that has all the right size pipes to change those.


    The white pipes are all PVC, black ones are ABS. You only need to know that if you are gluing them together. Each uses a different adhesive.


    If this is a manufactured home they use a cheap Air Admittance Valve that you should replace with a better one. Still, water should not reach the valve. I'm guessing that your drains are clogged otherwise there would be no overflow.

  • Eileen Eileen on Dec 02, 2017

    Very easy most of the pipes are screw in. You can buy each individual pipe. Turn your water off just incase. There will be residue water from the old taps. You could do each pipe one at a time. Just so it all goes back the same way.


  • San31669447 San31669447 on Dec 02, 2017

    Are you replacing them, because you are adding a dishwasher or garbage disposal? or just replacing because...

    take a photo of them at a few different angles, in our town the plumbing specialist at Lowe's will get everything together that you need and will assemble it to show you how to once you get home. But, any competent plumbing department specialist/employee should be able to help.


  • DORLIS DORLIS on Dec 02, 2017

    Unless you are young and can bend down that low, I would say call the plumber. Just make sure everything is our of the cabinets so you don't end up paying for him to take it all out. Also make sure you can do it quickly as the water to the house will have to be off.

  • Nancy Turner Nancy Turner on Dec 02, 2017

    I agree with Sandy. Take pictures so that you get all the pieces that you need. If in doubt on the size, take the T with you. The PVC pipe should be only hand tightened, so you should be able to take it off. Wi9th the pictures you should be able to get it back together in the right way without a problem. My moms place, somehow the drain pipe was put in the wrong place so the pipes go sideways instead of down coming from the disposal, so I have to take it apart frequently to clean gunk out that gets trapped. It was easy to take apart and put back together. Tighten the pipes together by hand with no tools, as the PVC will crack if too tight. Once you get them back together, turn the water back on and check each connection for drips by feeling them with your fingers. It will let you know if you got the pipes together straight with no leaks. Make sure you have a bucket of some kind handy just in case. It is not really that hard to not have the connectors not on straight the first time. Easy to fix, no worries. The people who work in the home improvement stores know their sections and can help you get all the right pipes you need.

  • William William on Dec 02, 2017

    Go with Ken and Sandy. Kitchen pipes are 1 1/2". Yours are screwed on with compression nuts. Best to take a few photos when you go and buy what you need. The people at the plumbing department can help you out. There are so many pipes and adapters one can go crazy trying to match things up from memory. The black one is Air Vent where no vent pipe to the roof can be run. It lets air to vent allowing the water to drain. Closes when there is no air to be released. It's not supposed to allow water to pass it. You may need a new one if it overflows.

  • Randy E Randy E on Dec 02, 2017

    Suggest you add shutoff valves to the small white tubes going to the water faucets above. Makes maintenance of faucets simpler. Water will have to be off at main supply to do this. Is that a bolt in the small white pipe to the right near the vertical drain section? Just asking cause metal corrodes/rusts. If leaking only and not cracked anywhere, new seals at joints may help. Definitely need to unclog Black drain pipe to prevent backup. The air intake valve at top of black pipe should be removable to run snake down there. Replace it if it leaks, as others say. Best to connect it to existing through wall roof vent if possible. May not be. Might try something like this to open drain? Use care though, Nasty stuff. From Home Depot


  • Elizabeth Elizabeth on Dec 05, 2017

    do what you feel that you are comfortable with ,Hi: What is the problem with the under the sink pipes? I see you have a container underneath so to me it means they are leaking somewhere. If that is the problem you don't have to change the pipes. There are products in the hardware store that can help you seal the leak. First identify where the leak is coming from, at what level it may not be from the pipes but from the sink drain, plumber's putty around it may have wore out or the drain is twisted. If you don't like the pipes and feel you need new ones take a picture of them with you and seek help at the hardware store. If you want to change the pipes yourself Home Deport, not sure what other hardware store has-Tutorials that show you how to do it. Also you tube has many people showing how to change pipes. Main advice do what you feel you are more comfortable with.