13 Things You Should Never Put down the Kitchen Sink

Even if you have a garbage disposal fitted in your kitchen sink, some things should never go down the drain. Getting into the habit of throwing food scraps down there will result in blockages, backups, and expensive plumber bills.

Trust me, there’s nothing fun about having your kitchen sink back up on a Monday morning, or your dishwasher pipes flooding the floor because the water had nowhere else to go. These issues can also make a serious dent in your wallet, as well as wasting water and energy.

We did our homework and gathered expert tips from home maintenance pros and plumbers to help you avoid common problems and keep your kitchen — and plumbing — running smoothly.

Coffee Grounds

It’s really easy to get into the lazy habit of putting coffee grounds down the sink. That’s a quick solution to get rid of them, right? Sadly not. In a drain pipe, coffee grounds don’t decompose easily and will build up over time — and then block your sink.

A better solution is to start a compost pile or simply put them in the trash (though we know that can often stink).

Grease and Oil

Grease, oil, and fat may seem obvious, but it’s still worth mentioning that you should absolutely not put any form of oil and grease down your sink.

Within minutes oil and grease will congeal and stick to your pipes, blocking other debris from going down easily. Worst of all, you have no idea where the build-up will happen. It could occur far down the pipeline, causing seriously expensive plumbing bills.

Remember to always pour excess oil into a container, let it cool, and then throw it away. You can also use paper towels to clear out the remaining oil in your pans before you clean them.

Egg Shells

Even partial eggshells are a no-go. Don’t throw them down your sink! They take a long time to disintegrate in pipes and collect with other debris to cause blockages.

Even if you put them in your waste disposal, they can blunt the blades over time. The better option is to throw them in the compost or in your trash.

Rice

Rice is difficult because some grains always seem to find a way down the sink. But you should do your best to prevent letting any get down the drain. Rice will expand even further than it already has during cooking, causing blockages in no time.

One grain won’t be the end of the world, but it’s wise to get into a habit of preventing it from happening.

Food Skins

Onion, celery, garlic, and any other vegetable skins can cause blockages and damage to your garbage disposal by wrapping around the blades, causing mechanical issues.

Failing to decompose fast, they can also act almost like plastic if they get stuck in your pipes. Once again, the trash or compost pile is your friend.

Plastic

OK, Captain Obvious here: you really don’t want to get lazy by letting a few bits of plastic fall down the drain. You might think garbage disposal will take care of it, but even the smallest pieces of plastic can cause havoc. As plastic builds up or gets stuck on debris, you’ll soon have a backup.

Paint

When you’re clearing up from DIY or some art, it might be convenient to pour the leftover paint down the drain — wrong. Dried paint in your pipes is the result and it’s a disaster for your plumbing, causing blockages and leaving chemicals in the local water.

Follow local guidelines for paint disposal, or throw it out if it’s dried completely. You can let it dry by leaving it in the sun with the lid off or by mixing it with cat litter.

Stickers

When washing fresh produce like apples and bananas, be careful not to let stickers go down the drain. They stick to pipes and other debris and don’t dissolve quickly, potentially causing blockages. If you get a block, you’ll need to call out a plumber.

These stickers can also cause issues at water treatment facilities.

Bones

It’s not worth putting fish and poultry bones through your garbage disposal, as they’ll damage the blades and mechanics. Sooner or later you’ll need to pay for repairs.

Sure, it might reduce the bones to smaller pieces, but that can still be big enough to cause blockages in the pipes. Instead, throw them in the trash!

Flour

Have you ever seen what happens when you try to mix flour or cake mix with water? It turns into a big messy clump. You wouldn’t want that in your pipes, would you? It’s going to end in severe backup and bad smells. Instead, throw it in the compost or trash.

Paper Products

True, paper disintegrates in water. But in tight spaces like pipes, it can get stuck on corners and debris and solidify with grease to cause a serious blockage. One or two small pieces might not cause an issue, but over time they will. It’s a habit you really need to cut out.

Vomit

I have a friend who once needed to throw up pronto. The kitchen sink was closer than the toilet bowl, so he opted for that. Next thing you know, last night’s meal was clogging the drain.

As you can imagine, that is a truly unpleasant block to clear up. So, I highly advise (on his behalf) to get to the toilet bowl first.

Medication

Medication is unlikely to cause a block in your pipes, as it generally dissolves easily. However, you should never pour liquids or throw pills down the sink as it will contaminate local water. Aquatic life in particular is then at risk of being affected.

Most pharmacies provide medication take-back services and that’s a much better idea.