Heating pipe expansion noise - fixed (I think)

[nothanks]

My house has an unusually long main landing, with straight pipe runs in the floor down the length of it. Since the old galvanised pipes were replaced with copper there have been dreadful expansion noises and several attempts at stopping them have failed. A while ago I thought about putting PTFE "U"s in the joist notches but didn't get the right tuit until today. A few hours work removing carpet and boards then cutting/bending/inserting 2" and 3" wide strips of 2mm PTFE into the notches seems to have finally solved the majority of the noise. In case it's of interest to others - the PTFE sheet is readily available on-line and cuts easily on a band saw or with tin snips. WTH didn't I do this 2 (or 3!) years ago.

[Fredxx]

After seeing a plumber, I've used felt bumf. Perhaps PTFE is a better alternative.

[nothanks]

I tried with felt, and bits of insulating sleeve, and enlarging the notches but nothing worked reliably. I even had expansion joints at the half way point. It's early days still, but the PTFE seems to have worked.

[John Rumm]

I found that felt/fibre style insulation pipe jacket also does the trick.

One thing to watch with long runs it that the pipes are not able to abrade themselves other other things as they slide around, as I found to my cost once:

[Andy Burns]

I repurposed some "horsehair" underlay, did the trick ...

[Jeff Layman]

An interesting tale. I wonder if copper pipes are not all created equal. Perhaps in the drawing process to create them the 22mm pipe ended up harder than the 15mm pipe, so it was the latter which wore away when they rubbed together. Otherwise, I'd have expected some wear on both.

[nothanks]

I tried just about everything except a full pipe sleeve - the pipes are

28mm so that would have needed too much of the joists to be cut away. PTFE isn't expensive and is easily cut and bent so I don't know why using it isn't commonly discussed. I opted for 2mm but it's available in a wide range of thicknesses down to 0.1mm.

probably have several places where pipes are resting on other pipes, but to sort it all "just in case" would be a humongous task so I will promptly forget about it, with one exception: the expansion joints. These are corrugated stainless steel, side-by-side, and have large ribs where the s/s is joined to the copper stubs. It would be sensible to put a PTFE barrier between them next time I have that bit of floor up.

>

[John Rumm]

That is actually an interesting point... there was at some point a change from the thicker walled fully annealed copper pipe of the past to the modern thinner wall "half hard" pipe... not sure when that was.

However looking at my end on photo of that bit of damaged pipe, that could well be the thicker wall (and hence softer) pipe.

[Brian Gaff]

Almost any kind of plastic works for this. In my immersion heater cupboard, it used to make some very weird and ghostly noises. The hardest bit was figuring out which point on the tank or pipes was doing it. I just gently prized up the point of contact with the surrounding wood and slid sheet of soft plastic under each one till it stopped. As to why this works, I can only guess that maybe it goes in jerks when on the wood, but is smoother on plastic. Now all I need is a way to stop the plastic gutters from groaning and clicking as the sun comes up in summer.... Brian