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Plumbing Repair - Clogged Drains

General Clogged Drain Information
floor drain Clogged drains are certainly a nuisance, but they don't always require a costly call to a plumber. There are some simple techniques that any normal homeowner can try.

Please understand: The instructions we are providing below are intended to be used as general information only. Techniques can vary, but we've tried to provide the most common repair techniques we possibly can. If you have any doubts you should attempt any of the procedures below, then we would recommend not doing so. Also, we suggest you wear rubber gloves; plumbing repair can get quite messy!

Tackling Clogged Drains - Material Suggested:

Sink Drains
Slow or stopped sink drains: There are many potential causes for a sink draining poorly. If you're experiencing trouble with just a single drain (as opposed to slow drainage on multiple drains or fixtures in addition to your sink, which would be an indication of a larger problem, and would most likely require using a large sewer snake system - see below), there could be a build-up of material that's been gathering in the drainpipe between your sink and the main line for some time that isn't allowing the water to drain adequately; very often, it's in the trap of the drain, which is usually fairly simple to remedy.

  • If your lavatory drain has a pop-up drain stopper, first remove that drain pop-up plug; it's possible the plug has hair or other material attached to it that's preventing the sink from draining. (There are many different types of drains, so removal of the plug or strainer will depend upon your specific drain.) Run water into the sink; if the water drains, you'll know the problem is that the drain plug is dirty or for some reason isn't allowing the water to drain adequately. Clean or replace the plug as needed. Be aware that sink drain plugs very often tangle with hair, which is a common cause of a slow drain; maintain the cleanliness of your drain and its stopper as often as you can.
  • If that doesn't solve the problem, then try running hot water for five minutes or so, as hot water can dissolve built-up soap or other similar products that may have dried or gathered into a partial blockage in the drain.
  • If your drain is still not draining the way it should, the next step will be to try an environmentally safe chemical drain opener. There are many different types available, so be sure to thoroughly read the product information before you purchase or use the product. Generally, fill the sink with a few inches of water to give the product room to work. Also, remember to run water into your sink for a few minutes if/when the drain reopens, to flush the opener from your system.
  • If none of the techniques above work, it's time to roll up your sleeves and dig in deeper. You can begin by trying a small suction-cup plunger to see if a few plunges dislodge the clog; however, this can sometimes be difficult in sink drains. Make sure to remove your kitchen basket strainer or your lavatory drain plug before you try. (Lavatory sinks usually have an overflow hole, too, and so this will have to be plugged off in some way so that the trapped water doesn't just spew out of the overflow hole.) Place the cup of the plunger over the drain; the rubber cup will seal against the sink bottom. Give the plunger a few plunges; this will put pressure against the water that's in the cup of the plunger and in the drain, which will hopefully destroy the blockage.
  • If the clog persists, you can try using a small drain auger such as a Mini Hand Snake. Techniques vary, but typically you'd want to feed the tip of the coiled snake cable into the sink drain a short distance, rotate it, feed it some more, rotate it, etc., until it's inserted as far as possible into the drain pipe. Give it a few more rotations, and then slowly pull it back out. Now run some hot water into the drain for a few minutes, to clear the lines and hopefully confirm the drain is draining successfully.
  • You may instead find it necessary to disassemble all or part of your sink's P-trap, so that you can try to clean it manually. To do this, make sure you have a bucket or pail handy to catch the water when it drains out of your sink. Some P-traps have a small plug on the underside of the bend, which is called a "cleanout plug" because it's there for this very reason. If you have a cleanout plug, remove it and see if you can clear the stoppage with an instrument such as a screwdriver (or perhaps a straightened coat hanger of a flexible cleaning brush); you may be able to pull the obstruction right out.
  • If you do not have a cleanout plug that you can unscrew, then you will need to remove the J-bend from the trap. Most J-bends have two nuts (one where the drain attaches from the sink at the "long end" of the "J", and another on the "short end" of the "J" where it attaches to the wall bend pipe); if you have a chrome-plated (or other finish) P-trap, you should consider using a rag or something similar to protect the finish of the nuts. Unscrew the nuts to remove the J-bend, as this is very possibly where the clog is located. At this point, the water should drain from the sink, so make sure you have your bucket positioned correctly. (If the water doesn't drain from the sink bowl, you'll know the clog is in the short drain pipe beneath the sink drain; with your bucket in place beneath the drain pipe, try poking a long, thin object down from the sink, to see if you can push anything out.) Inspect the condition of your P-trap, to see if there's any corrosion or thinning apparent, as you may want to consider replacing the trap anyway; check the drain washers, as well. Otherwise, use a flexible cleaning brush to clean out the bend, and then reattach; run hot sink water to flush any loose particles through and into the main line.
  • With the sink trap's J-bend off, you can also try using a water-powered drain-clearing device such as a Clog Buster, which connects to a garden hose and applies water pressure to push blockages through the waste line. Be very careful to read the instructions on such products very carefully, however.

Usually, one of these methods will clear a common, small clog from a sink's drain line. If the above suggestions don't work for you, then your clog may actually be further down the line. If you're courageous and confident, you can use a drain rootering system (often called a "sewer snake") to try tackling the larger problem of a clog in your main line on your own (see "Basic Augering Information" below); otherwise, it may be time to call a plumber.

A smart idea: If you find you're continually dealing with clogs in your sinks' P-traps, you may want to consider replacing your P-trap J-bends with a No-Clog Safety T-Trap, or installing an Add-A-Trap trap catcher; they allow for easy maintenance and removal of clogs, and also provide access to the drain line when valuable items have been dropped into the drain.

Dishwasher Drain Lines
Poorly draining dishwasher lines: A dishwasher drain line is another common clog. It's generally not considered to be as much of a problem as a clog in a larger drain, and sometimes it's not even realized it's happening. But it can actually result in - and be indicative of -- other, larger potential problems down the road.

By code, dishwashers require an "air gap" for their drain line. The air gap usually looks like a chrome (or other color) cap that's mounted on the sink, next to the faucet, and the dishwasher's drain line connects to it beneath the sink. The air gap introduces a break of air into the flow of the dishwasher's wastewater, which prevents the "dirty water" from potentially flowing back down the drain line and into the dishwasher, contaminating the fresh water supply.

The dishwasher's primary drain line is a rubber hose that runs from the dishwasher and attaches to the air gap's barbed inlet, beneath the countertop. Another, (usually larger) second drain line then runs down from the outlet of the air gap, and attaches into the sinks drain line. If you have a garbage disposer, the air gap line will attach to a barbed nipple on the disposer body; if you don't have a garbage disposer, the air gap drain line will attach to a barbed nipple on a drainpipe beneath the sink. The wastewater should flow through the dishwasher drain line, past the air gap, and into your sink's drain system; if all is flowing well, you won't even realize it's happening.

However, if the wastewater exiting the dishwasher is excessively dirty (filled with food particles, for instance), a clog can develop along the dishwasher's drain line. Generally, when a clog occurs, it's due to a build-up in the air gap's drainage line, near the barbed nipple on your drain pipe or disposer. This is indicated by water spewing out of the actual air gap and into the sink (which is actually another emergency function of a dishwasher air gap), instead of passing through the lines undetected and into your drainpipes beneath the sink.

This situation should be repaired as soon as possible. If left draining inadequately, the clog could worsen, and it's even possible the gray water can back up into the fresh water if the dishwasher's drain water is not being allowed to drain as it should.

  • Have your bucket handy, and then disconnect the line from the disposer's or drain pipe's barbed inlet. It's usually attached with a hose clamp, so you'll need to loosen the clamp by unscrewing the tightening screw. Position your bucket so that both the rubber hose and the drain nipple can drain into it.
  • Disconnect the other end of the hose from the air gap, so that you can make sure the run of hose is clean. Again, allow it to drain into your bucket. You can now take the hose to another faucet (at a completely different sink, or perhaps to a hose bibb outside) and run water through it if necessary; clean up any mess that may have spilled into your sink so that it won't cause a problem in that drain, too.
  • With a screwdriver, poke around inside the barbed nipple on the drain line or disposer to dislodge any build-up that has accumulated there. With your bucket in place, you can run a small amount of water into the sink bowl to clear the clog from the disposer or drain pipe. (The water and waste should exit through the drain pipe, but your bucket will be there to catch any that might dribble out of the barbed nipple.)
  • Reconnect your hose to the air gap's outlet and the barbed nipple on your drainpipe or disposer; tighten the screws on the hose clamps, as needed.
  • To test, you can run your dishwasher for a cycle. The wastewater should no longer spew from the air gap, but should again drain undetected into the drain lines beneath your sink.
  • Most new garbage disposers have a plug on the inside of their barbed nipple inlet, so that there's no leaking if the homeowner doesn't have a dishwasher drain line attached. If you experience a drainage problem with your dishwasher only after a new disposer has been installed, it's likely your disposer's plug is still in place. Loosen the hose clamp and remove the hose from the disposer's barbed nipple (with your bucket ready to catch any water draining from the hose), and then pop the plug out with a screwdriver.

Tub Drains
Slow or stopped tub drains: The most common culprits for a clogged tub drain would be loose hair and soap coagulation. Even those blessed with a full head of hair do lose a few hairs every now and then (and some of us less blessed lose more hair, more often!); additionally, soapsuds and residue can also build up in a tub's drain pipe just as they can in a sink's drain. (Again, if you're having trouble with more than one drain at one time, the clog may be in one of your main lines; in such cases, a drain snake would have to be employed - see "Basic Augering Information" below.)

  • If your tub drain has an exposed stopper plug, you can try removing it from the drain to see if it needs to be cleaned. There are different types of tub stopper plugs, and removal of the stopper varies; sometimes they unscrew by turning the top of the plug, other times they may have a gripping knob that will unscrew and expose a screw that can be rotated for removal. There are many other possibilities regarding removal technique, as well.
  • You can also try running hot water or using a chemical drain opener to try to clear the drain, as outlined in the sink info above, which should take care of simple blockages such as hair and coagulated gunk. Plungers are a bit easier to use in a tub than in a sink; make sure to plug the overflow drain, though, to prevent the blocked water from spewing from the outlet. Give the plunger a few strong plunges to try to push the blockage into the main line to free your water drainage; for your last plunge, push down a bit harder and then pull back forcefully, as this can sometimes bring the clog back out of the drain. (If so, dispose of the mess in the garbage; do NOT try to flush it down your toilet, because you might then just transfer the problem from one fixture to another.)
  • It can be very difficult to access a bathtub's P-trap, even under the best circumstances. If your tub is on the first floor and there's a crawlspace beneath the tub, or if the tub is on an upper floor with an access panel in the ceiling below, you may still be able to get to the trap to see if the clog is there. It's not always possible to access a tub's drain trap, however (for instance, when the tub has been built on a concrete slab).
  • Some older tubs have what's called a "drum trap", which is designed exactly as it sounds; it's a drum container that can be opened for cleaning. The lids of drum traps can be pretty tough to remove, however, since these types of traps are usually quite old; before struggling with your wrench, it may be a good idea for you to first use some sort of thread-penetrating oil, which can dissolve a lot of the build-up on the threads to make the lid easier to unscrew. Then, try to locate the cause of the blockage in the drum or in the nearby lines.
  • If you have the more modern, J-bend style of P-trap, you can also try removing the J-bend by unscrewing the two nuts on each end. Make sure to have your bucket ready, as the water in the tub may drain out once the J-bend has been removed. Use a flexible cleaning brush to clean out the bend, and then see if you can find any blockages in the nearby line. When you're done, reattach the J-bend and run hot water into the tub's drain to flush any loose particles through and into the main line; hopefully, this will confirm the stoppage has been removed from your line.
  • With the trap's J-bend off, you can also try using a water-powered drain-clearing device such as a Clog Buster, which connects to a garden hose and applies water pressure to push blockages through the waste line. However, you'd have to plug your tub's overflow, or the water will spew back out and into the tub. It may be difficult to block the overflow sufficiently, as well.

Often, one of the procedures outlined above will permit your tub to drain successfully. However, you may have a blockage deeper within your drain system that would require more aggressive action. Aside from trying to use a drain rootering system (AKA "a sewer snake") yourself to clear a clog in your main line on your own (see "Basic Augering Information" below), it may be time to contact a plumber.

Toilet Drains
Slow or stopped toilet drains: Toilets have a special type of trap, called an "S" trap, which is built into the body of the toilet bowl. Most often, toilets get clogged within this trap, as it is narrow and tight. Always be careful of what you try to flush down a toilet. Products such as ear swabs, for instance, can lodge and actually web together, blocking the passage of wastewater; also, feminine hygiene products can swell up in the trap and clog the toilet.

  • The best tool you can have for a clogged toilet is a plunger, and the best type of plunger to use on toilets is a force cup plunger; this type of plunger uses a large bell-like cup, which forcefully pushes the water within the cup into the drain trap. Before you begin plunging, make sure you have sufficient water in the bowl to allow the plunger to work. (Rather than flushing the water from the tank into the bowl if it's too empty, which could possibly cause a messy overspill, you can always add a few large cups of water from your faucet into the bowl instead.) When you're ready, place the cup of the plunger in the drain at the bottom of the bowl and give the plunger a few forceful pushes. Pull the plunger back towards with great force, to see if the water exits your bowl and out the drain or is pulled up back into the bowl. If it doesn't work the first few times, keep trying.
  • If you just can't get the plunger to unclog your toilet, you can try using a closet auger, which is a type of mini snake that's specifically designed to clear tough clogs from a toilet's trap. Closet augers usually have a long body with a length of wound cable inside, and a crank handle on the end; hold the auger at its body with the crank towards you, and carefully feed the cable into the mouth of the drain. Turn the handle while feeding the cable further into the drain. When you feel it catch or become tight, crank the auger a few more times and then slowly pull the cable out of the drain; hopefully, you'll pull the clog out with it.
  • If the clog persists, it is probably time to call a Plumber. When the simple repair techniques above don't clear a toilet's clog, a large sewer snake would have to be used to clear the sewer lines further down (simple info on which is listed below) or the toilet would have to be pulled from the floor, and these may not be procedures a homeowner would want to attempt themselves.

Basic Augering Information
Augering your drain line with a sewer snake: If you've confirmed the trap and nearby lines are clear but the water in your sink or tub still won't drain (and/or your toilet still won't flush successfully), it is likely you have a blockage further in the system, and even perhaps in one of your larger drain lines. At this point, you may want to think about calling a plumber. But, if you have access to a sewer snake and want to try clearing the blockage yourself, here are some helpful tips:

  • Try to determine a point of access as near to the blockage as you can. If the blockage is near a specific fixture, you can remove the J-bend of the fixture's trap and feed the snake cable through that opening. Or, if it seems the blockage is within a long run of sewer pipe, there should be a cleanout access nearby; if so, you should see a cleanout plug that can be removed for access.
  • Feed the cable along slowly until you feel it bump into the obstruction; try to snag the blockage by slowly turning the snake's handle clockwise, which should rotate the tip of the cable into the clog. This should entangle the clog, and allow you to try to break it up.
  • Once the clog is hooked, push and twist the cable to dislodge or disintegrate it. After you've successfully destroyed the blockage, run cold water into the line to flush the pipe.
  • When you're done, reattach the J-bend to the P-trap or replace the cleanout cover.

Helpful Hints
Helpful tips to maintain your drains: Of course, the best defense is the good offense preventive maintenance provides. Keep your drains clear before clogs even occur. There are environmentally-friendly drain and trap cleaners available that will reduce the occurrence of stoppages with monthly application. Follow the instructions on the product you're using, as the frequency of the application will vary. Also:

  • Be careful what you dump down your kitchen drains. Even if you have a garbage disposer that's powerful enough to grind up your leftovers, the mulched food will still end up in your drain lines and can build into a clog; scrape the food off of your plates and into the garbage as best as you possibly can. Only the remaining sauces and small bits of food should be washed into the drain, and only if you have a garbage disposer.
  • If you have a dishwasher, make sure the dishes have been scraped off and rinsed before placing them in the dishwasher. Otherwise, the remaining debris will eventually clog your dishwasher and its drain line, resulting in additional drainage issues (with your air gap, your sink drain, etc.).
  • Do NOT pour grease into your sink. The grease will quickly coagulate, especially when cold water hits it, and will almost certainly develop into a clog.
  • Maintain your sinks by pouring very hot water (boiled, if possible, so that it's as hot as possible) down the drains a few times a month. This can dissolve soap and grease that's building up.
  • Keep the stoppers in your lavatory drains clean of hair and build-up. Not only can this cause your sink to drain slowly, the hair can eventually untangle from the stopper and cause a clog further down the drain.
  • Again, only flush waste and toilet paper down a toilet; that's really all a toilet is designed to handle.