Plumbing Drain Noises - Diagnosis & repair of glub-glub, burbling, and other drain sounds

How to diagnose & fix plumbing drain noises - plumbing drain sounds may explain drain problems
- What causes noisy plumbing drains? How to investigate & repair plumbing drain sounds
- Add sound insulation to reduce plumbing drain noise transmission in homes
- Drain noise complaints due to plumbing vent problems
- Blocked plumbing venting & gurgling or slow plumbing drains - glub glub noises from toilets or other fixtures
- Gurgling drains may indicate a partially blocked or sluggish sewer piping or private septic system
- Sounds of running or dripping water in a building drain
- Normal plumbing drain sounds, and normal but annoying sounds
- How to find the source of plumbing drain sounds
- Drain noise complaints due to a V200 anti-siphon valve
Questions & answers on Diagnosing the Source of Plumbing Drain Noises and on reducing plumbing drain noise in buildings
References

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Plumbing drain noise diagnosis: this article discusses how to identify different types of plumbing drain sounds, including the cause, diagnosis, and cure of different sorts of plumbing drain noises - how to find, identify, and diagnose the source of plumbing drain, waste, and vent piping and plumbing fixture sounds. We discuss how to add sound deadening insulation around new work or into existing plumbing pipe routes in buildings. That "blub blub" or "glug glug" noise you hear from a building drain might mean that there is a problem with the drain system itself, such as a partial drain blockage, a drain venting problem, a drain odor problem, or even a failing septic system. This article explains how to determine the causes of plumbing drain noises, and we refer to key companion articles that assist in that diagnosis, and we include plumbing noise cures.

How to Diagnose Sounds of Gurgling or Other Noises in a Building Drain Piping System

As we explain in more detail at PLUMBING DRAIN NOISE REPAIR, we divide plumbing drain and fixture noises into two groups:

Plumbing defect noises associated with plumbing system problems or defects whose identification and diagnosis is discussed here at PLUMBING DRAIN NOISE DIAGNOSIS and at PLUMBING DRAIN NOISE REPAIR.Our complete list of various plumbing system noises is at PLUMBING NOISE CHECKLIST , a sub-topic of building NOISE / SOUND DIAGNOSIS & CURE.
Normal (but annoying) plumbing system noises that will be corrected by noise transmission control or sound insulation are discussed at SOUND CONTROL for PLUMBING, a section of SOUND CONTROL in buildings where we describe controlling the transmission of noises in buildings.

Gurgling or "glub glub" sounds in building drains are usually heard at or near an individual plumbing fixture such as a sink or shower.

Inadequate or missing plumbing vents & noisy, gurgling, or slow plumbing drains

If a gurgling sound is heard at a sink or shower drain only when a nearby toilet is flushed, or at a sink or shower when a nearby tub is draining, we'd suspect that the building drain-vent system is inadequate.

This photograph shows a multiple-trap drain on a building sink - forming a double "S-trap" which lacks venting and also is very prone to clogging.

In addition to watching for eccentric home-made plumbing traps like this pair that are likely to cause bad sink, shower, or tub drainage, check for the following:

Plumbing fixtures installed with no vent connection at all, such as a bathroom or kitchen sink that use an "S" shaped plumbing trap.
Vacuum breakers at drains: Plumbing fixtures originally installed with no vent connection to which a (sometimes permitted) local plumbing vent/vacuum breaker (such as a "V-200 plumbing vent) usually installed right under the sink to permit air to enter the plumbing drain line as needed but intended to keep sewer gases from exiting that same drain - a one-way valve. If the valve is defective or "stuck", inadequate, or improperly installed this problem may occur.
Plumbing fixtures that are installed too distant (perhaps more than 5') from the vertical plumbing stack vent that is supposed to serve them.
Island sink vents: special case of this plumbing venting problem can occur at island sinks installed in kitchens. Special drain vent piping details are required to assure that such isolated fixtures will drain properly.
Plumbing fixtures whose vent diameter is too small in the building or above the roof line - resulting in frost clogging in freezing climates
Plumbing fixtures whose vent line in an attic was not extended to outside the building (lead to indoor odors and potentially dangerous, explosive methane gas accumulation.
Plumbing vents clogged by insect nests, animals, or vent material deterioration such as transite plumbing vents

Blocked plumbing venting & gurgling or slow plumbing drains

A plumbing drain line could itself blocked, as opposed to a blocked or inadequate plumbing vent line. In the case of a partially blocked plumbing drain, case all of the fixtures served by that drain line will always be slow to drain.

When weather and safe access permit going onto a roof (or using the services of a professional for that purpose), check for blocked building plumbing vents such as plumbing vents that may have become blocked by an insect nest, birds nest, or as shown in this photo, a frog. In freezing climates, check in winter to be sure that the plumbing vents are not being blocked by frost or by snow-cover.

See Cold Weather Septic Odors or Sewage Odor Diagnosis.

Gurgling drains may indicate a partially blocked or sluggish sewer piping or private septic system

If the outside sewer line is partially blocked, or if waste piping to a septic tank or from a septic tank to a drainfield is partially blocked, the building drains may appear to work normally until there is a surge of usage such as an increase in occupants or when using a washing machine.

In lighter usage the waste and wastewater flow down into the main drain line or sewer line where they are in effect, "stored" while the waste slowly seeps past the partial blockage. As wastewater seeps past the partial main drain blockage a gurgling sound may be produced at fixtures in the building as air is drawn intermittently into the drains - an effect more pronounced if the building drain vent system is inadequate.

In heavier usage of building fixtures, such as when there are many occupants or when doing laundry, the additional volume of water may first cause this "gurgling drain" symptom to be more pronounced, and as the blockage worsens, the building drains may actually back up during heavy use. This condition can also produce sewage smells or sewer gas backups into a building.

At More Information our articles offer further diagnostic advice for blocked drains, blocked septic systems, or inadequate plumbing vent systems. Also see SEPTIC BACKUP PREVENTION (private septic systems) or see SEWER BACKUP PREVENTION (buildings connected to municipal sewers) and also see the health and safety concerns discussed at SEWER GAS ODORS.

Sounds of running or dripping water in a building drain

Continuous Plumbing Drain Sounds like Trickling Water or Water Dripping Noises

Photograph of a house with missing plumbing vents

Trickling water sounds coming from a building drain or fixture might indicate a fixture leak problem. A sound of dripping heard inside a drain line, or the sound of continuous running water may be heard. Both of these can indicate that a plumbing fixture in the building has a water supply leak which is leaking into the fixture.

If the drip and sound are occurring outside of the fixture or its drain, such leaks are usually discovered pretty quickly when water or leak stains appear in the building.

But a plumbing leak that causes a toilet to run, the only clues might be noticing that the toilet fill valve is sometimes re-filling the tank even though no one has used the toilet, or one might hear water running in the building drains, or if the property is served by a private septic system, the system may experience flooding and backups.

Normal plumbing drain sounds

Hearing the sound of running water in a building drain is not likely to indicate a problem with the drain system itself. In older buildings where cast iron and steel drain pipes were used, not much sound normally is heard: even the sound of running water, say when a shower is running or when a toilet was flushed. But in a more modern structure that uses plastic or copper drain piping these materials can transmit the sound of running water to the building interior. Builders can reduce sound transmission from plumbing lines by enclosing them in insulated chaseways.

We have also found cases in pipes in a building transmit sounds from one area of the building to another. We've also found that electromagnetic fields generated in a building, say by a bank of electric meters located in one area, can be transmitted to other building areas through metal piping.

Normal (but annoying) plumbing system noises that will be corrected by noise transmission control or sound insulation are discussed at SOUND CONTROL for PLUMBING, a section of SOUND CONTROL in buildings where we describe controlling the transmission of plumbing noises in buildings.

How to find the source of plumbing drain sounds

An experienced plumber can often diagnose these problems quite quickly since s/he is more familiar with plumbing problems than most homeowners. But if you want to do some drain sound detective work yourself here are some steps that might help.

Identify the fixture: Identify which fixtures are producing the sound: is it all fixtures in the building? If so we suspect a system drain problem or that the building has only a single inadequate vent system or no venting at all. If the sound occurs only at a specific fixture, we suspect a blockage or vent problem local to that bath, kitchen, or laundry area and its vent or drain piping.
Flush the toilets: Blocked or inadequate vents can produce slow drains as well as noise. But if none of the drains are slow, but you hear gurgling at a nearby sink when the toilet is flushed, take a look underneath the sink. If the trap is shaped like an "S" over on its side, the sink is probably not vented and the flushing toilet is trying to draw air into the drain line from the nearby sink when the toilet is flushed.

If the trap is shaped like a "P" over on its side, with its horizontal outlet running into the wall, we can't see if the sink is really vented or not, but the style of plumbing is more modern and it might be vented. If the trap is some crazy combination of multiple bends and parts, call a professional plumber to unsnarl the installation since such jury-rigged plumbing traps are likely to be problematic.
Look for other appliances or systems that are sending water or waste into the building drains: dishwasher or clothes washer cycling, even a heat pump or air conditioner condensate pump cycling to send water into the drain system may make periodic drain noises.
Look in the attic for a plumbing drain line that passes vertically up from the floors below and out through the roof. If you can't find one, the building may not have proper plumbing vents.
Look outside for plumbing vent pipes poking up through the roof in one or more areas. If you see a plumbing vent at one far end of the building where baths are located, but no plumbing vent stack pipe over the end of the building where a kitchen or laundry are located, those rooms may have been built without proper plumbing venting.
Check out the septic system (or main sewer line connection): for signs of backup, blockage, or odors outside. Effluent breaking out to the surface, muddy or soggy areas, smelly areas, may indicate that the septic system, or part of it, are failing and are periodically not accepting waste.
Call a plumber to investigate further by visual inspection, drain pressure tests, or using a drain camera or scope

How to repair problems causing plumbing drain sounds

Suggestions for repairing or reducing plumbing drain noises and sounds are at PLUMBING DRAIN NOISE REPAIR. Excerpts are below.

Repairing Missing plumbing vents

Adding missing plumbing vents:: The photo shows a large house with only one plumbing vent visible (click the image for a larger view).

We didn't see vents over or anywhere near the portion of the home which houses a kitchen and bath. While it might be possible for the building to have a working vent system, the combination of its age and other details raised a question worth investigating further.

If we find that there are other "short" plumbing vents which were covered by the deep snow in this photo, they need to be extended.
When plumbing vents are simply not provided, the proper repair is to install missing vent piping, up through the building and through its roof. In old buildings you may see vertical plumbing lines that were added, in plain view, inside the living space. But modern construction "hides" these pipes in the building walls. If you want to install modern, hidden plumbing vents, and providing your plumber has shown you that in fact they're missing, you may want to wait until other more extensive interior remodeling are in the works.
Vacuum breaker plumbing vents - V-200™: Meanwhile the plumber may install an illegal vacuum breaker to improve drainage - these products can be added wherever a drain is having trouble getting enough air to flow properly, but in most jurisdictions their use is subject to approval by the local plumbing inspector.

Repair frost-blocked plumbing vents

Fixing a freezing plumbing vent line in which the plumbing vent becomes partially or fully blocked by frost or ice where it extends above the roof in a freezing climate, probably requires the installation of a larger diameter vent from the attic out through the roof.
First check for leaks: before installing a larger diameter plumbing vent line, make sure that there is not a hot water leak into the plumbing drains or continuous shower use. A water leak into the drain system can result in continuous movement of water vapor or "steam" upwards in the vent system too. In freezing weather that water vapor may condense and then freeze in the outdoor portion of the plumbing vent system simply because it's passing that way continuously.
Too-short plumbing vent stacks: A plumbing vent stack which is too short above the building roof can be blocked by snow and then stop venting. But that does not mean that we should be installing very tall (3' to 6') plumbing vents. Except in areas of unusual snow depth such heights are probably much higher than needed. The plumbing vent stack above a roof needs to be high enough to never be covered by snow, not more. I speculate (really am guessing) that perhaps if a vent is TOO tall in a cold climate, moist air never will escape at its top because the added cold length of pipe actually encourages freezing.

Other Plumbing System Noises

Noisy water heaters are discussed at WATER HEATER NOISES.

Stop Sewer Gas or "Sulphur Smell" Odors Caused by clogged plumbing vents, drains, or septic systems

Clogged, partly clogged, slow drains or a partly-blocked, failing drainfield can also cause odors when the surge of water from the washer causes a gas backup in the system: see Diagnosing Clogged Drains for more detailed advice along that problem path.

Septic additives like Rid-x won't fix a problem with building vents nor sewer odors, and are generally not recommended anyway - see Additives & Chemicals for septic system maintenance. Are septic products needed? Are septic treatments legal?

Frequently Asked Questions (FAQs) about the causes & diagnosis of plumbing drain noises

Question: Why do Our Drains Gurgle When the Heat Pump Switches to Cooling Mode?

When we switch our water source heat pump from heat to cool, the bathtub drains periodically make, loud, gurgling sounds. What is the cause and how do we cure this problem ? We are on well water & we do have a septic system. - G.B.

Reply: Check that Heat Pump Condensate Drain First

A competent onsite inspection by a plumbing or HVAC expert usually finds additional clues that help accurately diagnose a drain gurgling noise and heat pump problem. That said, here are some things to consider:

I am just speculating wildly, but a plausible explanation is that the heat pump condensate line may be draining into a pipe that is transmitting noise back to your tubs. If you're sure it's gurgling and not a vibration from something mechanical, that's my first guess.

More obscure: if the condensate drain (cooling systems produce condensate by taking moisture out of the conditioned house air during the cooling cycle) is not properly piped, a fan coming on could cause a vacuum or backdraft up the condensate drain line that might also make noise - but I'd think you'd hear that in either heating or cooling mode, while in contrast, your heat pump would only be producing indoor condensate in the air handler when it is in cooling mode.

Question: What can we do about the loud noises coming from the plumbing drains in our home?

We moved into our home 6 years ago and whenever the ensuite toilet is flushed we can hear the water very loudly go down through the pipes. Recently, whenever ANY toilet is flushed or a sink drained on the 2nd floor we can hear the water travel down the pipes. What is the cause and how can we fix it? Thank you. Kathy in Calgary

[Our photo, left, shows ABS drain/waste/vent piping (DWV Piping) in a ceiling pipe chase in a New York home during a recent building addition project, courtesy of Galow Homes.

Reply: explanation of plumbing drain noise transmission and suggestions for adding sound insulation

Kathy, I am guessing that your home is fairly new and that the drain piping is ABS plastic (or PVC plastic) run in walls or pipe chases that at least in part pass through building interior walls or ceilings. Those pipes are indeed noisy and the noise is easily transmitted to the room interiors. By contrast, older buildings that used cast iron drain piping find there is less noise transmitted by wastewater running through the drains.

The level of noise transmitted is a combination of the acoustic transmission properties of the thinner walled plastic piping, the proximity of the piping to occupied space, the absence of noise insulation around the pipes, and details of exactly how the pipe was routed and supported. Specifically, pipes that are in solid contact with building framing or drywall transmit more noise. Pipes that were suspended using acoustic-isolating hangers transmit less noise to the building interior. As we cite at PLUMBING NOISE CHECKLIST,

According to the Canadian CNRC, "Noise reductions up to about 15 dBA can be obtained relative to systems where no resilient mounts are used for pipes."

What to do now to reduce drain pipe noise?

Because it would be costly to tear out ceilings and walls to mess with pipe supports and routing, I'd seriously consider blown-in insulation into the areas where these pipes are routed. Typically you'd fill the ceiling joist or wall stud bay where the pipe is contained - fill it completely, a step that significantly reduces noise transmission.

Our photo (left) shows what the ceiling pipe chase (and surrounding areas) looked like after a professional blown-in foam insulation job in the same New York home. Subsequently of course drywall was installed over these surfaces (we do not leave foam insulation exposed because of fire hazards). After this foam was installed there was no plumbing noise detected in this area when the toilet was flushed in the floor above.

Use foam insulation because it will flow around the piping into odd-shaped spaces and will fill the pipe space completely. Don't worry, your foam won't have to fill an entire wall or ceiling space, just the space where the pipes actually run, typically 16" or 24" wide by the length of ceiling section or height of wall section by the typical joist or stud width, say 10" or less for 2x10 ceiling joists, and 5 1/2" for 2x6 wall studs or 3.5" for 2x4 wall studs.

Nevertheless the volume of these spaces is more than you can fill consistently, adequately, and economically in a do-it-yourself project using little spray cans of foam purchased at a building supplier. So I recommend hiring a foam insulation installer.

Of course your foam installer should not have to tear off drywall nor foam as extensively as I show in our plumbing chase foam insulation photos above. Rather it will probably be quite possible to fill the appropriate pipe routing cavities with foam by injecting foam through very small openings spaced along the route of the piping. The result will be no more than occasional 1/2" diameter or less holes to patch and paint along the pipe route.

Question: Vacuum breaker found under the kitchen floorboards

We are currently renovating a victorian house and found a strange machine under the kitchen floor boards. After reading your article,it seems what we have is a vacuum breaker,so thanks for the info. - Anon

Reply: hidden traps, vacuum breakers, grease traps, drain troubles

Thanks for the tip. Indeed hidden plumbing traps, vacuum breakers, grease traps, etc. can add to the time and trouble we encounter when tracking down drain noises, odors, or clogs. A photo would be a help to other readers. If you can provide a picture of what you found, send it to us using the CONTACT link found at the left of any of our web pages.

Question: Drain glug glug, klug klug, & whirring noises: why do I hear a clug clug sound when the toilet is flushed?

Why do I hear a "clug,clug "sound when the toilet is flushed? The toilet is upstairs and the sound is coming from the basement on the other side of the house - Karen Canning

I have slow drains and saw a 1 foot x 1 foot soggy spot over my septic field. When one person is in the shower for more than 15 minutes (teenagers) or if the washing machine is running, we get the glug, glug sound. Toilets do not like to flush right away, they fill, then suddenly drain out. Suggestions? - Susan in Florida

We are a single family two story (plus basement) home in central Connecticut with city water and sewer. Yes, our home has a proper through-the-roof plumbing vent pipe.

Recently my wife noticed a strange whirring sound coming from the (upstairs) bathtub drain. Honestly, I thought she was nuts, but sure enough now I notice it also. Think of a muffled police siren; whirr-whirr-whirr. Lasts about 5 to 10 seconds, then may or may not happen again within minutes, and so on. Any time of day; a few nights back I woke at around 3:00 AM and, while using the bathroom, there it was. I had not yet run any water, flushed the toilet, etc.

Any hints as to what could cause such an odd sound to emanate from the bathtub drain? It is the only fixture in the house where we have noticed this. I am confidant that it is not related to the hot water heater which is of the indirect-fired type. Our high-efficiency gas-fired condensing boiler has a small motorized condensate pump which empties into the main branch (cast-iron) drain pipe in the basement, but I am pretty certain the noise is not coming from that either.

Home was built in th 1920's with typical plumbing for that era. Bathroom was remodeled two years ago, so bathtub and related plumbing is all relatively new. - Carmine in Connecticut

Reply:

Karen: if you hear a "klug klug" when the toilet is flushed it may be a blocked or missing plumbing vent. Sometimes a slow partly blocked drain will do that too.

Carmine:
The whirring sound from the bathtub drain may also be due to a blocked vent, especially if it happens when the toilet is flushed or other drains are in use. A home like yours, built in the 1920's may also not have plumbing vents provided at all fixtures, or the vents may be undersized or even clogged. Even if some fixtures were updated it would be unusual for 100% of their drain runs and vents to have been replaced.

Susan:
That glug glug glug sound along with slow drainage is often water draining slowly past a blockage somewhere down the septic or sewer drainage system. If it were a venting problem unless something just clogged a vent, it would have always been present. Combined with the wet spot in the yard sounds like a saturated drain field but until you do some investigating we don't know if it's as inexpensive as fixing a broken or clogged pipe, or replacing an entirely saturated failed septic drainfield.

CLOGGED DRAIN DIAGNOSIS & REPAIR can help diagnose tracking down a clogged drain and distinguishing between a local drain clog and system drain clogging: knowing where the clog is located will define the type of drain repair needed.

SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR can help you diagnose what's going on with a blocked or partly blocked septic system or drainfield. .

Question: Bubbling & bubbling noises at basement floor drain

My house is about 40 years old, and we did remodeling 3 years ago. Starting last week, I noticed a bubbling noise lasting a few seconds from the basement floor drain. This noise happens every minute or so without obvious reasons, even when no water in use. All draining of fixtures seem to be working fine, no slowness or noise. No gas odors smelled.

Do you have any idea what might cause the noise and how to fix it? - Peter in Toronto

Reply:

Bubbling in a basement floor drain might be a slow building drain that is backing up; even if you haven't just run a plumbing fixture, if, for example, you flushed a toilet earlier and all of that wastewater emptied just fine, but really just ran into a larger-diameter sewer pipe under or outside or still near the building, where then it ran into a partial blockage, what would happen is that the wastewater would drain past that blockage slowly, causing gurgling or bubbling sounds.

When the noise seems to have stopped, go flush a toilet and wait a few minutes to see if you hear the sound beginning anew. If so we may be on to the right diagnostic.

Question: Air handler A/C condensate drain & glugging sound in bathtub drain

My air handler seems to be constantly draining and I'm getting a glugging sound in my upstairs bathtub drain. Is it related and is my air handler close to frozen? I don't see any leaks in the attic although I haven't gone all the into the attic and inspected the air handler. I did close most of the air duct vents upstairs to force the cold air downstairs, could I have possibly froze the air handler considering it's 110 most days and the AC is almost constantly running? - Randy in Mesa

Reply:

Randy your note suggests perhaps your air conditioner condensate is draining improperly into a plumbing vent line and that in turn that line (or the condensate drain itself) is partly clogged.

Or you have a separate problem with a slow bathtub drain or bad bath venting.

If the glugging sound occurs when you flush a toilet in that same bathroom I suspect the drain or vent is clogging.

If your air handler cooling coil was iced over you'd see the effect as loss of airflow out of the air supply registers, or you can see the icing and frost by inspecting the air handler interior (power off first for safety).

Question: Loud drain noises when toilet is flushed

Reply:

Kathy your question is a common and important one about how to avoid plumbing drain noises in buildings. I've added my suggestions and some photos in the article above. Please take a look - just above this comment box - at your question and my reply, and let me know if you have further questions or suggestions for us or other readers. Thanks. DF.

Question: Glub glub when my shower/tub combo drains, sounds at the toilet

I live on the first floor of a small apartment building. When my shower/tub combo drains, I hear a "glub glub" sound like it's coming from the toilet. Today, I walked in to find that the bathmat was soaked and there were remnants o something brownish that had backed up into the tub. I can't figure out how/when it happened, though. Any idea what's going on and what I should do? (My landlord will probably tell me to fix it or pass the cost onto me.) - Anon

Reply:

Anon the glub glub sound you describe is typical of a partially blocked main drain or a blocked plumbing vent system. It sounds as if you have a blocked drain and sewage backup into the tub. Your lease will most likely describe who is responsible for

- keeping the plumbing system working
- cleaning up unsanitary sewage backups due to plumbing problems

Question: Sound of water constantly coming down pipes in master bedroom, maybe from upstairs A/C ?

I have lived in on the 12th floor of a 13 story building, constructed in 1928, for 10 years. About a month ago, I started hearing what sounded like water constantly coming down the pipes in my master bathroom. The problem was noted as likely being from my upstairs neighbor's ductless air conditioning system, which apparently cools via pipes and flushes water down the same pipe as the toilets. No fix has yet been arrived at for that problem. In addition, the air conditioner contractors who came to look at the issue indicated that such noise shouldn't be audible since the pipes in question are cast iron.

At the same time, I can now also hear my upstairs and downstairs neighbors' use of their plumbing - from toilet flushing to tap use. This seems odd, not only because I've never heard it before in all the years I've lived here, but also because the pipes are cast iron. We did a "test" and you could hear the noise of the toilet on the first floor flush all the way in my unit - 11 floors away! I am being told by my building super that such plumbing noises are "normal," but that is not consistent with my experience nor, I believe, the materials in question.

He thought there may be air in the system so turned the water supply off then back on, but it made no difference. I am finding it difficult to get any response from my building management. I am going to get in my own plumber but wondered if you had any ideas? - Nicola

Reply:

Nicola,

A noise of water running pipes can be annoying but my first worry would be an actual leak;
And I agree that it's usually tough to hear water running in cast iron piping.

On the other hand, noticing a change is usually an important diagnostic. See if you can track down what happened a month ago - a service call, a plumbing change, something. That'll be a useful clue.

I don't think air in the drain system would explain drain noises; there's always air in the drain system.

Reader Follow up:

Thank you for your response. On the changes, one thing that occurred right about when I started hearing the noises - and I may not get the terminology right - there had been an uncharacteristically huge rainstorm here and the waste pipe for the building was not big enough to handle the capacity so there were overflow problems, like water running out of people's toilets on the first floor (apparently the pipe doubles in function; I live in a large city).

That pipe for the building was replaced, I want to say from a 6 inch to an 8 inch; I could be wrong on the size but I know it was increased. I asked the building super if there could be a connection, and he did not appear to think so. I have also checked with one of my downstairs neighbors and he does not think he perceives plumbing noise other than from inside his own unit. The only other apparent "change" was that my upstairs neighbor who is apparently not usually around in the summer (though she has lived above me all 10 years I've been here) started using this ductless air conditioning system that continually flushes water down the same pipes used by the toilets.

I wonder if this could have precipitated a problem? What is most puzzling to me is that now my neighbor has been requested to turn her air conditioning system off, it is definitely apparent that I am hearing not only toilets flushing but also the use of running water, such as from showers - and loud enough to be heard outside the bathroom. In other words, the noise does not appear to be confined to one particular pipe.

Since my first query, it has since been suggested to me that perhaps I have a dried trap (maybe due to a clogged vent) which is magnifying the noise of water through the system. I am still in the process of getting a couple good plumber recommendations. In the meantime, I don't know if you have any further opinion based on these facts? Thank you. - Nicola

Reply:

Nicola,
Two items to check further:

It is trivial to check for the effect of a dry plumbing trap- just pour a pint or more of water into every plumbing fixture to be sure every trap is filled. I am not considering the possibility that you have a drain with no trap at all or an s-trap that loses it's seal because you report your noise complaint is a change.

About sound transmission changes around a building drain, if there was insulation that has become wet or was removed you may hear more drain noises. Check for those conditions.

Question: Clothes washer drain noise into bedroom wall piping - should we insulate the wall?

Hi,
I recently moved into a new-build apartment. There is a flat above me, and the residents just moved in. Their utility room is directly above my bedroom, and I was up four times last night as their washer drained water into the pipe, which runs through the wall in my bedroom.

The builders have told me it's a 6-inch pipe, which seems massive for one washer and maybe a sink! They are suggesting pumping insulation into the wall, but I'm worried - will this fix it? Why did they install such a big pipe? Would that be making it more noisy than it needs to be? - Emma

Reply:

Emma, the large diameter drain may be because it's carrying other fixtures, or to avoid clogging; in any case, insulation can reduce noise transmission.

Question: Why do my toilets go glub-glub when the shower is on?

What would be the cause? I get the "glub-glub" in my toilets while the shower is on, shortly followed by the shower backing up and the toilet not flushing. I have snaked the outlet towards the septic to no avail. I'm sure that the phone call to the plumber will follow, but would like some idea before I look like a complete idiot. - Eric

Reply:

Eric: that glub glub noise followed by clogged drains means most likely that you have a blockage or partial blockage further along in your main sewer line than your plumbing snake would reach.

Question: Gurgling or glub glub sound in drains and slow drainage - septic tank was just cleaned and I heard water pouring back into the tank ..

i just had my tank cleaned out 2 months ago & now i think, but don't know how to tell if there is a problem with building vents. i getting a Gurgling or "glub glub" sounds in the drains and slow drainage, we also have had very heavy rains this month, after the tank was pumped out i could here water pouring back into the tank, how can i check the vent pipe from the roof to the basement, there r no openings from the roof to basement what to do? - Tony

Reply:

Tony, the bad news is that when water pours back into a septic tank during pumpout that suggests that the drainfield is saturated, not working, and may need a costly replacement. Sometimes, especially after heavy rains, surface runoff can be saturating the drainfield. In that case the "fix" may not require drainfield replacement, but rather the installation of an intercept drain system to keep surface and subsurface runoff away from the septic drainfield.

Your slow drain problem can be from a blocked main drain or from a flooded septic tank and backing up drainfield.

Question: dripping sounds in drains above my apartment

I moved into an apt. on the first floor 3 months ago. I have been recording dripping sounds (about 1.5 drips on an average per hour)and notified the manager to no avail. When someone has come to listen (3 times) of course nothing happens but they only stay 10-20 minutes. The dripping sound is over the toilet and sink area.

No apparent leaking coming from the under-the-sink or toilet areas of the apartments above me, according to maintenance. No crawl space above 1st floor apts.; only 2nd floor apts. have crawl space between their ceilings and roof. I've been told the only way to investigate is by cutting a hole in the wall. I imagine the cost to do that is keeping them from further action. The dripping sound is loud and sounds like water dripping on wood, or manmade product.

On an average it drips about 1.5 times per minute. It can drip 40-50 drips/second and go 20-30 minutes without dripping at all. The complex is approximately 12 years old. A single boiler for each building. Each building has approx. 20 1-bdrm apartments. The buildings are 2 stories, 2-sided, 10 apts on each side = 20 apts. in each building. I've been in other apartments on both the lower and upper floors. No one else in my building seems to have this problem. Any ideas? - Jean Smith

Reply:

Jean, what you describe sounds like a slow leak into the ceiling over your bathroom. A small leak may take some time to show up as stains on the ceilings or walls below. Sometimes there may also be a leak that drips into a drain pipe itself - that'd be lucky in that the risk of hidden rot, mold, or other damage is less.

Question: Glub glub sounds on the kitchen sink when the water is turned off

In my 16 year-old house, several months ago I started hearing gurgling or "glub blub" sounds on the kitchen sink when the water is turned off. If I only run the water to a few seconds then I don't hear the sound. But if I run it at full speed for a minute or longer, after all water is drained down the pipes I hear the sound.

I recently had a new garbage disposal and faucet installed, and the plumber suggested I just needed some drano to clear the pipes for that noise to go away. I used foaming drano last night but the noise is still there. The water drains fine, so I don't think there is any blockage, but that loud blub sound for a minute after every faucet usage is quite annoying. Any ideas? - Zvez

Reply:

Zvez,
The glub blub sound you describe often is a hint that a drain is partly clogged in your system. If the drain blockage is pretty far from the sink itself, you may find that you can fill and drain the sink just fine - as its water is simply filling the open pipe between the sink and the blockage. From there the water drains slowly past the blockage, making the sound you describe.

We hear similar noises when the building vent piping system is clogged - in this case the noise is caused by air entering the piping as the fixture is draining.

Question: Gurgling from kitchen sink, snaking the drain didn't help

Hello, appreciate the info. on your site! About 6 months ago, I cleaned out the pipes under the sink due to a very slow leak from our garbage disposal. The leak was due to a bad pipe seal... A few months later, we started to hear the gurgling sound coming from our kitchen sink (sometimes even after just a little water has passed through).

I do also think that there's something with our A/C since over the summer there was some leaking of water coming from the outside drain (it's tied to the inside drain in our guest bathroom though and guessing it should only drain there?). Long story, short, I snaked the drain from the main sink pipe (the point just after the pipes from garbage disposal and 2ndary sink converge) and it did not help. I'd used the blower 3 or so months ago (to blow air through the pipes)... and this seemed to resolve the issue for a week or so. Any help is appreciated! - Joey

Reply:

Joey your description suggests that there may be a partial drain blockage on the main house drain between the building and the septic field or sewer line. A blockage can also send water backing up from the outside drain as you described. If you have a septic system, the problem may be in the drainfield. Check the levels in the septic tank if you're not on a sewer system.

Question: drain noise from water running down sink tailpiece into the drain trap - how do I fix this?

Just got a new vessel sink installed and trap/drain under sink had to be replaced due to reconfiguration. Lots of noise from water running down the tailpiece and into P trap. PVC used. How do we fix this? - Pam

Reply: check first for proper venting, then consider sound insulation for plumbing drains

Pam:

First you will want a plumber to confirm that the new sink installation has been connected properly to a plumbing vent stack. Second, presuming the piping is all correct and the drains are not blocked but run freely, if the drain noise remains a local problem in the building, you can consider adding sound insulation around the drain piping.

Watch out: while it's trivial to box in and insulate a building drain, be sure to provide an access cover to permit inspection of the drain for leakage and to permit the trap to be removed, cleaned, replaced. We don't want water from a leaky trap spilling into the insulation enclosure lest we risk a mold and rot problem.

Question: foul odor from sump pit smells like sewage

I have two issues that may (or may not) be connected. There is a persistent foul smell that comes from our sump pit- it smells like sewer water and occasionally really smells up the basement with this foul smell. I have had the main line that exits the house to the main sewer line in the sewer scoped and there was no apparent leak. . I ran a hose at full throttle down the vent and had no return so it seemed like it was all clear.

The sump pit hose that runs to the main line has a check valve. The sump pump drains/ejects rain water and also water from our washing machine that drains into the pit. When the sump pit ejects its water it enters the main line out to the street (this is code in my village). However, when the sump pit activates I can hear a gurgling sound from my kitchen sink. There is no smell from the kitchen sink however. - David

Reply:

David,
A smelly sump pit may be due to sulfurous groundwater, a drain line leaking into the sump system, or gases backing up from the sewer line. The gurgling under the kitchen sink can indicate a partly blocked drain, or if you're confident that the drain is free, a venting defect.

Even running water down the vent line to show that it doesn't seem blocked won't detect improperly routed plumbing vents. For example if a sink or other fixture is too distant from the vent stack it may not vent properly and you'll get that gurgling in the drain. Also if your kitchen sink is installed in an island countertop, special vent piping arrangement is needed to vent properly.

Question: drain noise complaint: glub glub from kitchen sink drain when washing machine empties

A few months ago we started having loud "glub glub" noises from our kitchen sink drain when the wash machine empties. House is 6 years old (we built it), all sink drains are properly vented with Studor mini vents, and we have a septic system which has not been emptied.

The kitchen drain is the furthest away of all the drains, and washer drain pipe joins the main drain pipe immediately downstream from the kitchen drain pipe. No sounds have been observed from any other sinks, toilets, etc. However, there are a few other wacky occurrences which may or may not be related.

Recently we had a problem with one of our toilets not flushing...it would swirl and fill up with water, and very slowly go down. I attempted to flush nearly 10 times holding the handle down until it finally went and have not seemed to have problems since.

Also, a few summers ago I noticed a sewer smell in the back yard in the vicinity of the septic cover, and the location of the perceived odor changed, seemingly with the wind. I could not find a spot on the ground that was wet, muddy, or had any odor, but I could often smell it in the same area

. I had wondered if the ground could have settled enough to crack the pvc pipe that leads from the house to the septic tank and cause a blockage. Last summer, though, I didn't smell it once. I've opened the cover a few times to see if it looked full, but it didn't.

Our neighbors are plenty far away so I know it couldn't have been from them. My wife runs a daycare in our home, so she uses plenty of water, and I've wondered if a child may have flushed an object down the toilet. With everything I'm reading on your site (which is great, by the way) I'm not sure the first thing to check short of calling a plumber. - Mike

Reply: good news, bad news, about noisy sink drains when washer empties

Mike, it's an axiom in diagnosing drain noises and sluggish drains, that if the problem is a basic design and installation one, most often (not always) you'd have had these complaints since the building was first constructed. I say "not always" because some plumbing installation mistakes such as improperly sloped drain piping or use of improper tees and wyes in drain connections can work ok at first but may eventually lead to drain clogging. Still, those mistakes usually show up early in the life of the building.

But if the slow plumbing drains and plumbing drain or vent noises show up much later in the life of a building, our first guess is that either a drain has become clogged or partly clogged, or if the home is connected to a private septic system, the septic system is in failure mode - slowing or even refusing to accept effluent outflow from the septic tank.

On occasion, the good news is that the problem is just a blocked or damaged drain or vent pipe. The expensive problem is a failed septic.

Take a look at CLOGGED DRAIN DIAGNOSIS & REPAIR for suggestions on how to proceed.

Question: The neighbor's roof vent is so noisy we hear the toilets flush next door

We have a covered patio that faces the side of our neighbors house. We can hear his toilet flush through the vent pipe on his roof. Is that normal? We have never noticed it in other houses we have lived in where our outside space was in close proximity to our neighbors bathroom vent pipe. It is so annoying and embarrassing when we are outside. Is there anything we can have our neighbor do to eliminate the noise? Thanks, Bonnie

Reply:

Bonnie,

Presuming that there are normal distances between your patio and the neighbor's plumbing vent roof pipe, what you describe is unusual. I wonder if perhaps the neighbor has

a problem with their plumbing vent system or drains leading to gurgling noises?
new high velocity low-water using flush toilet that happens to be unusually noisy? (Some toilets that use an air blast to help scour the bowl while using less water can appear noisier than traditional WCs.)

You might ask the neighbor if flush noise is a problem inside their own home, or if there is a drain problem - if the answer is no to both cases, ... well I'm not sure what recourse you have without having to ask the neighbors to reroute their drain vent to another roof location that sends less noise your way. I'm continuing to research and will report further here.

Question: Drain Noise Complaints Traced to V-200 Anti-Siphon Valve Installation

Just bought a 40 year-old house. Sump pump drains into city sewer. V200 plumbing installed on drain pipe up in the rafters about 16 inches above pipe. After the sump pump turns off a loud burping or gurgling sound is heard. It lasted about 10 seconds. I changed the V200 for a new one and the same sound occurs but now for only 4-5 seconds. Any ideas? thank you - Louis

Sorry. In that last comment i shouldn't have said rafters but rather between the basement floor joists. I also meant a V-200 plumbing vent (also called anti-siphon I think) - Louis

There is ONE vent coming out through the roof for the plumbing in this house (two bathrooms and one kitchen) while the bathroom in the bedroom has a vent that terminates in the attic. The kitchen sink also has one of these V-200 things. Any way to stop the noise without venting this pipe through the roof? Given the construction it wouldn't be easy. Thanks for your help Dan

Reply:

Louis the V-200 or "cheater vent" is intended to allow air INTO the drain line when needed, and may be making noise during that function - as water runs down your drain line, and presuming that your building lacks proper vent piping to outside above the roof, the V200 is breaking the vacuum and allowing air into the drain as needed.

Louis a plumbing vent that terminates in the attic should have been run to outside the building to avoid a potentially dangerous sewer gas problem indoors.

It's common for vacuum-breaker "cheater vents" like the V-200 to be retrofitted in older buildings where the original plumbing did not include or did not include enough plumbing vent piping.

The V200 - which is indeed an anti-siphon valve) and similar products, are a stopgap or retrofit measure that we use when there is just no economical way to get a proper plumbing vent installed. But I don't blame the V200 anti siphon vent itself for the noise problem. That's a feature of the type and location and routing and size of plumbing fixtures and drains. In my experience noise complaints around anti siphon valves are rare.

You could try moving the piping and anti siphon valve a bit, or you could try some sound insulation around it - just be sure to leave a way for air to get TO the anti siphon valve or it will stop working.

...

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Developments in Noise Control, NRCC, National Research Council, Canada, suggestions for noise control, sound transmission through block walls, plumbing noise control, noise leaks, and sound control advice. Web search 01/17/2011, original source: https://www.nrc-cnrc.gc.ca/eng/ibp/irc/bsi/90-noise-control.html
Eric Galow, Galow Homes, Lagrangeville, NY. Mr. Galow can be reached by email: ericgalow@gmail.com or by telephone: 914-474-6613. Mr. Galow specializes in residential construction including both new homes and repairs, renovations, and additions.
Sewage Odors in Wet or Cold Weather - Septic Odors or Sewage Odor Diagnosis & Repair Guide for diagnosing and eliminating cold weather sewer gas odors,
Sewer Gas Odors diagnosing, finding, and curing septic tank and sewer line smells. I welcome questions or content suggestions for these topics.

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How to Diagnose Sounds of Gurgling or Other Noises in a Building Drain Piping System

Inadequate or missing plumbing vents & noisy, gurgling, or slow plumbing drains

Blocked plumbing venting & gurgling or slow plumbing drains

Gurgling drains may indicate a partially blocked or sluggish sewer piping or private septic system

Sounds of running or dripping water in a building drain

Continuous Plumbing Drain Sounds like Trickling Water or Water Dripping Noises

Normal plumbing drain sounds

How to find the source of plumbing drain sounds

How to repair problems causing plumbing drain sounds

Repairing Missing plumbing vents

Repair frost-blocked plumbing vents

Other Plumbing System Noises

Stop Sewer Gas or "Sulphur Smell" Odors Caused by clogged plumbing vents, drains, or septic systems

Frequently Asked Questions (FAQs) about the causes & diagnosis of plumbing drain noises

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Question: dripping sounds in drains above my apartment

Reply:

Question: Glub glub sounds on the kitchen sink when the water is turned off

Reply:

Question: Gurgling from kitchen sink, snaking the drain didn't help

Reply:

Question: drain noise from water running down sink tailpiece into the drain trap - how do I fix this?

Reply: check first for proper venting, then consider sound insulation for plumbing drains

Question: foul odor from sump pit smells like sewage

Reply:

Question: drain noise complaint: glub glub from kitchen sink drain when washing machine empties

Reply: good news, bad news, about noisy sink drains when washer empties

Question: The neighbor's roof vent is so noisy we hear the toilets flush next door

Reply:

Question: Drain Noise Complaints Traced to V-200 Anti-Siphon Valve Installation

Reply:

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