“I’ve got a question about rattling pipes. About 2 months ago, I noticed that when I turned on the faucet, a pipe somewhere in the walls of the house shook and made a pretty loud roaring sound that was strong enough to be felt in vibrations. It only lasted a few seconds. Over the next few weeks it got worse and would go on for 3-5 seconds. Then it seemed to ease up (no more vibrations, shorter duration) and not occur every time I turn the faucet on, but it never did go away. Should I be worried about this? Is there any way to fix it? Thanks!” – Gargouille, WYSK Reader

NV: Hi Gargouille! Rattling and roaring pipes, ay? Does the rattle sound more like a low slow banging or rapid machine gun fire? Any whining or squeaking? Hissing or tapping? I’m laughing to myself because this reminds me of those AAMCO commercials where the customer is standing in the repair shop imitating bizarre car noises to the mechanic.

to do listFunny stuff, but the truth is, sounds are very telling – and not just the sound, but also where and when it makes the sound that can help diagnose a problem.

In your case, the rattle happens when you turn your faucet ON and it’s coming from “somewhere in the walls.” Based on these two factors, I’ll deduce that when the faucet is turned on, the movement of the water running through the lines is rattling a pipe somewhere – a pipe that has loosened from a strap that once held it firmly in place. A loose pipe is the noise culprit! But then again… it could be air in the water system. Or is it something else entirely, like water hammer?!

Gargouille, what we have here are the same dreaded diagnostic dilemmas faced by mechanics, tradespeople, and doctors alike! You ask, “Should I be worried?” Maybe. Again without a definitive diagnosis, it’s hard to answer, but I will say, if any vibration is strong enough it can’t be good for your pipes and fittings.

Ok, deep breath. Try the simplest solutions first.

If I were you, this is what I’d do:

  • secured pipesHave someone turn the water on and off while you try to identify exactly where the sound is coming from. Test both the hot and cold water from the faucet.
  • When you locate the banging pipe, hopefully it will be exposed (like in the basement or crawlspace). Secure the pipe by adding a small piece of foam or rubber pipe insulation to the pipe and re-strap it.
  • If the banging pipe is behind a wall and can’t be accessed, there’s not much you can do without opening up the wall. You can try to wedge padding or wrap insulation at each point the pipe emerges from behind the wall or at shut-off valves.

If this last procedure doesn’t help, try purging the water system, which will void any trapped air in the pipes, as well as replenish intentional air in air chambers. I know that sounds counterintuitive, but air chambers (vertical pipes installed close to the shut off valves) are designed to prevent “water hammer” by absorbing pressure up in the chamber, and if these chambers get filled with water, they stop working. (I’ll get to what “water hammer” is shortly.)

To empty your water lines:

  • Shut off your water at the water main.
  • Starting from the highest faucet from the main (or farthest in a single story house), turn on all of your faucets, flush your toilets and briefly turn on your washing machine and dishwasher, until all the water is voided from your system.
  • When the water stops draining, starting with the lowest faucet from the main (or closest) shut them off, re-flushing the toilets too.
  • Now slowly turn the main back on. Water will be back in your lines, and air back in the air chambers!
  • You may have to repeat this procedure to get it right, and don’t be surprised if air sputters out when you turn the faucets back on.

Mind you, countless sounds can indicate a myriad of plumbing issues. Reviewing them all here would be a major yawn fest. That said, I will discuss two of the biggies – water hammer and HIGH water pressure.

Water Hammer pipesWater hammer – This is a specific problem with a distinctive loud repetitive banging sound that occurs when a faucet or valve is shut OFF. If it’s bad enough and left uncorrected, water hammer can loosen and even break fittings and valves! It’s caused by an abrupt stop of water flow at the stopping point (a faucet or shut-off valve). The pressure bounces backwards through the water and creates that hammering sound. Emptying the system of water (detailed above) can cure water hammer. If it doesn’t, it’s time to call in a pro.

Water Pressure Gauge pipesWater pressure – The maximum recommended residential water pressure is 80psi. (We have our municipal water systems to thank for how much pressure our water has when it reaches our home.) Water pressure that’s over 80psi can really cause plumbing problems – like literally cause fittings to burst! You can test your water pressure with a water pressure gauge (around $10 at the hardware store). To test your water pressure, screw it on to a hose bib (spigot), turn the water on and read the gauge. If it fluctuates over 80psi, call in a pro who will simply install a pressure regulator at your water main. (If only getting my blood pressure under control were that easy!)

So now Gargouille, if your pipes go bump in the night, or in the middle of the day, you’re all cool on how to calm the clatter. Thanks for your questions!

Norma sig

Got A DIY Question? Ask-The-Expert!

If you have a DIY home repair, maintenance or improvement question for Norma, now is your chance to ask-the-expert and have her answer. Your burning question may just be the “star” of an upcoming Fix-It Friday column.

Add your question to the comments section below or email it to Women You Should Know.

Fix-It Friday is an exclusive Women You Should Know® editorial series authored by seasoned veteran of home improvement, Norma Vally, the former host of Discovery Home Channel’s series “Toolbelt Diva” and a show on Sirius Satellite Radio by the same name. The weekly column is designed to inspire women – weekend warriors, aspiring handywomen, and even seasoned DIYers – to take on home repairs and maintenance projects with confidence and gusto.