Mystery that is driving me mad. About 3 weeks ago I noticed a pulsating humming noise in my house. Of course it is much louder when the house is deadly quiet like when I want to go to sleep but cant. Have resorted to having TV on to drown out this annoying sound but the TV keeps me awake.
I initially called the plumber and he thought it was my gas hot water system so it was replaced as old one was 18 years old. Still hummed. Next I got the gas people out to change regulator on gas meter as gas meter had been replaced a couple of months ago. Yay it went away for 3 days. It has been back worse than ever for the last 10 days. Plumber has been out twice. He did hear it so Im not going mad. He has unscrewed my sewerage pipe thingo ( I think) in the back yard to see what happens.I have asked the gas company to change the gas meter but still waiting on that. Know I will probably have to go through all the utilities. Eventually I may have to call the EPA. I am sending this from Australia.

It sounds like a transformer. It could be a meter. It could be in your house, unless you really turned off the main breaker electric.
My house has 2 transformers next to the circuit panel that hum loudly when on. They were installed over 40 years ago for outdoor 12V lights or something and were never used, I think. I just keep the switch off.

Thanks but I did turn off the main switch. Had a smart meter installed a few months ago. Had my ear up to everything including electric meter and walls, gas meter, alarm system etc. It just seems to be in the air. Its very odd.

A transformer out on the street?

Have underground power and the nearest box is right at the end of the street but I haven't ruled that out yet

From speedball1:
The problem is caused by the ballcock trying to fill while water is seeping out of the tank. The sound you hear is the washer vibrating against the seat of the ballcock. First check there linkage between the flapper and the flush lever. It should have 1/4" of play when your tank is filled. Next feel the flat side of your flapper. Does it have wavey edges? Do your hands come away black? Replace it if it does. And last check the seat itself. Any nicks or rough spots? If so click on back. There are replacement seats that glue right over the old one and are easy to replace. One of the above should take care of your howling. This happened in a new house some years ago. Only at night and in the early morning. They thought the house was haunted and were about to move out. I caught it in the powder room toilet. It would vibrate and the pipes in the wall would pick it up and carry it all over the house. Hope this helps Tom

There are countless other explanations here and on other online sites, including closed heat vents and EMF from nearby.

No I showed my plumber your comment and he has just fixed my toilet after the humming started so its not that.

I have been investigating thoroughly but haven't come up with a plausible explanation yet.

I too have this problem over the last few months have been trying to find the source of the noise and it is almost impossible to pinpoint where it stems from but seems so much lounder at night and more annoying because it is not a constant noise! Turned off electriciy at source no luck last night turned off water at source, still heard it. Next thing, I was going to try that toilet ballcock thing, have also read that I should check the water pressure but if the water is turned off completely shouldn't that stop the noise temporarily even if the pressure is too high or low?

Also what is EPA?

You would think so about the water but then Im not an expert. Someone suggested turning off water and opening hot and cold tap. Was going to try today but I have someone playing loud music. Let me know how you go with the ballcock thing.

Environmental Protection Authority

I already tried turning off water and opening hot and cold taps, no result. When the noise woke me again this am was wondering if it might be roots of trees in the pipes under our house, we did have this occur years ago and the city brought in something to clear them out. Where we live there a lot of large, old trees surrounding the house so am thinking of perhaps getting this done again - now the city does not pay for it anymore and I think it is going to be expensive - if I knew it would solve problem wld be worth it. Do you have large, old trees around where you live?

My estate I live on is 18 years old and while not new its not really old either. Not a lot of really old trees round here. Its such a catch 22, do I spend money to try and solve it and will it solve it? I read about someone having vines that touched their house and when they cut them down it seemed to stop. I have a tree that touches my house on the side it seems to be more noticeable and when I get chance I am going to cut down the branches that touch. We have to try anything.
Found out yesterday that the gas people had cancelled my request so the lady I have spoke to has put another request in.
I must admit since my plumber has opened up my sewerage outlet at the back, that while it hasn't gone away it is less noticeable. I am going to call him today. It does seem to be more pronounced the lower I get to the ground.
Are you in USA?
I hope together we may be able to solve this.

I live in Montreal Canada and yes I REALLY hope we can find a solution to this sooner than later, helps to know other people (unfortunate for you) have this problem as well! I don't think cutting branches near house will help but anything is worth a try, please post anything that helps you. Meanwhile tonight I am going to hardware store to get that ballcock changed (fingers crossed)This is about the last thing I can try before getting into the expense of a plumber, I will mention what you did opening the sewerage outlet at the back, but we do have quite a bit of snow so don't know if that would be possible now. Was that a big job? How long did it take your plumber?

It was very easy. He just unscrewed it and left it open. My plumber, luckily hasn't charged me for the couple of hours he has been out and says he won't which is lovely of him. He said since the noise has become less noticiable after doing that that he will put a cap on my poo pipe which is on the wall near my bedroom.
Must admit I am getting sleep now. My son has come back from his dads and heard it but he is one of the lucky ones that says he found it soothing and helped him sleep. Lucky he wasn't here when it was louder or we would have two obsessed crazy people. Lol
Have just found too that the water treatment plant has just installed two generators about the time my noise started (about 5kms away) to grab biogas from the sewerage plant. But you would think it wouldn't just be in my house. Something to ask my plumber I guess.

Good to know, I will get my plumber to try this and the cap thing and see how that goes. I never thought of branches touching the roof iether but I guess that would cause a vibration/humming noise too. Lucky you sleeping I'm still up through the night when the noise is constant, it's not so bad but when it comes and goes it wakes me. Someone said it's like someone blowing on a coke bottle, is that the same noise you hear?

Don't have the answer, but would like to share the same issue. We don't have any mature tree's around the house. It is truly the oddest thing.. it sounds like a cat purring, but more rhythmic in nature. Somebody told me to call an electrician, but not sure who to call?

I have the same problem in 2 houses, a friend also can hear a low pitch an annoying noise. Sometimes I can´t even sleep.


Could it be due to this?

Mysterious noise pollution is known as The Hum

http://www.ctv.ca/CTVNews/ExclusivesSciTech/20020923/stevenson_noise_pollution_020920/

Yes it could very well be the noise known as "The Hum". Are your neighbors bothered by it also> Back to you, Tom

Yes this sounds exactly like it and very interesting article. I now sleep with a ceiling fan on in my bedroom at night but as the weather gets colder it is not as pleasant to do but prefer this to having my sleep disrupted with this noise!