I inherited an IKEA sink and plumbing (boooo), and today I took it apart to clean it out due to clogging.

Unfortunately, it is now leaking no matter how hard I try to put it back together.

I believe the problem is that IKEA-proprietary downspout is too short to properly fit into the P trap's U pipe. Just the tip (haha) barely fits in to the U pipe, not enough for a proper connection. I've tried all sorts of ways to fit it in, but it twists and contorts the other pipe connections causing leaks in the other side of the U pipe and in the connection to the main drain pipe going into the wall.

How can I elongate the downspout so that it can fit at least 2-3 inches into the P trap U pipe?

Does IKEA use a standard diameter pipe?

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  • 1
    Your images are on the small side.
    – Nelson
    Sep 5, 2023 at 2:16
  • 1
    @Nelson oops updated the thumbnail sizes thanks
    – radlinsky
    Sep 5, 2023 at 2:56

2 Answers 2


Look for a "Slip-Joint Extension Tube" at your local hardware store. This is a very common part.

The standard sizes are 1.25" and 1.5". Get one of each if unsure.

example part

  • Thank you! I'll look for that!
    – radlinsky
    Sep 5, 2023 at 2:52
  • Take your downspout with you!
    – Huesmann
    Sep 5, 2023 at 11:47
  • Thank you Robert, this worked for me. FYI for others, the IKEA downspout is 1.5" diameter (measur from outer edge to outer edge)... I also had to replace all the rubber washers in the setup. The existing washers were a bit funky.
    – radlinsky
    Sep 7, 2023 at 22:02

Do you have drawers that snug up against the p-trap in the vanity? When I install the ikea sinks I use abs p-trap and only keep the piece that you say is too short. With the standard abs pipes you just need the 1 1/4" slip joint piece and you can make your p-trap shorter or taller easily.

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  • No, but now that you mention it, my wife has been asking me to remove the doors and install drawers instead. You have a good idea. If I'm going to be messing around with the plumbing anyways, I might as well use ABS and make as much room for the drawers as possible. Are you still able to disassemble your set up to clean out clogs at the sink drain? I can't tell from the photo if your ABS is glued together or screwed together in your set up.
    – radlinsky
    Sep 5, 2023 at 9:38
  • It has the large diameter screw hub so yes I can still disassemble. Sep 5, 2023 at 15:19

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