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Why Are the Pipes Under My Sink Curved That Way?

Have you ever had a child stump you with a question that seems simple on the surface, but is actually difficult to answer when you have to put it into words? Most of us have; children wonder about things adults often take for granted, such as the color of the sky… or the shape of home plumbing.

“Why does the pipe under the sink have that funny curve in it?” We don’t know if a child has ever asked you this question, but we’d wager that most adults don’t have a good answer. We’ll give you one, and help you better understand your home’s plumbing at the same time and why you need that curved pipe taking up valuable storage space in your cabinet. If you need more than answers—you need repairs—then look among the plumbing services in Salt Lake City, UT to find Design Comfort.

The p-trap

That curved J-shaped pipe is known as the p-trap, and it serves the function of preventing sewer gas backflow from your drains. When water runs down your drain, it flows through the p-trap without obstruction, but when you shut off the water, a small amount of liquid remains in the p-trap. This water forms an air-tight seal against air from further down the pipe from coming up through drain. Without this water plug, sewer gases from decomposed matter in the drain waste vent would come back up through your sink drain and create a noxious smell in your home. The sewer gases can even harm your health in large doses. That simple curve in your pipe makes home life much more pleasant.

You need to make sure that the p-trap has a water seal inside it. Usually this only requires running the water in your sink regularly, so it isn’t something you’ll need to think about often. However, if there is a sink in your home that rarely receives use, the p-trap can dry up because of water evaporation. If you notice sewage smells coming from a sink you don’t often use, run water through it to restore the plug—and try to run water through it at least once a week.

P-traps are where clogs usually develop in sinks: they catch hair, soap scum, and grease. Sometimes you’ll need a professional plumber to clean out your p-trap, wither with hydro-jetters or by removing the pipe. Make sure you let a professional handle this job: trying to work on a p-trap yourself can get messy.

We hope this has answered your question (or your child’s) about the curved pipe under the sink. It may take up space you could use for storage, but life without it would really, well, stink.

When you need any plumbing services in Salt Lake City, UT, call Design Comfort!

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