"Understanding Your Home" by Building Inspector Mark Visser
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Slow or Clogged Kitchen and Bathroom Drains

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Normally, kitchen sink drains do not become clogged easily because of the high volume of water navigating the p-trap.
Kitchen waste is mostly organic and is flushed out quickly especially if the dishwasher drain is connected to kitchen sink drain. Just make sure that this small diameter drain is connected to the drain ahead of the p-trap.
Vanity basin drains are a different story. It does not take long before there is a build-up of soap scum, toothpaste and hair in the p-trap. There are a few thinks you can do yourself to unclog a drain before calling in a professional.
Before you start, place a container below the p-trap to catch water and debris.
- Some p-traps can be removed by unscrewing both ends using channel lock pliers.
- If the p-trap can not be removed but has a clean out on the lowest part of the trap, cleaning is easy. Just unscrew the plug and with a wire hook pull out the mess.
- If there is a pop-up drain, remove and clean it as well as. Sticky debris can get caught on the pop-up parts and cause a slow drain.
If the trap has no clean out or cannot be removed:
- Use a plunger.
- Pour down a mixture of 1/2 cup of baking soda and 1 cup of vinegar. Let it stand for a few minutes. Finish off with a hot water flush.
- Pour down a chemical drain cleaner. (personally, from an environmental point of view, I don't like the idea of flushing chemicals down the drain. Also, chemical drain cleaners can erode pipes, so use them sparingly.)
- Use an air burst drain cleaner. This cleaner uses an accelerator (air, gas or carbon dioxide) to "bomb" the obstruction. These cleaners are most effective if the obstruction is close to the drain opening. Play it safe and wear eye protection when using the air burst drain cleaner.
If none of last four methods remove the obstruction you will have to the cut out the p-trap and install a new one.


Slow drains are annoying and you want to prevent it from happening as much as possible. It is easier to prevent a slow drain than to clear a blocked one. I have listed a few do's and don'ts.

DO's and DON'Ts
- Use your finger or end of the toothbrush to dissolve blobs of toothpaste before it goes down the drain.
- Once a week fill the sink with hot water, then pull the drain stopper for a good flush to remove any scum build-up.
- Pop-up drain parts should be cleaned regularly to remove any unwanted "hang-ups"
DO NOT pour grease down the drain. The grease will line the inside of the drain, pop-up drain and p-trap. Other stuff, like hair, will stick to it creating an unwanted clog.

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