Banging Bathroom pipes

[Jane]

I have a question regarding banging bathroom pipes. We live in a newly constructed house...it's about 6 months old. We notice that about 30 min to 1 hr after we finish taking a shower in our master bath (2nd floor), we hear a single bang from the water pipes (we assume). We may hear it again 5-10 minutes later. Does anyone have any idea what causes this and if the fix is easy? If it's easy, we may try to do it ourselves rather than call our builder. I have read several postings describing banging when the water is turned on or immediately after it's turned off, but this does not describe our situation. Any thoughts would be greatly appreciately.

Thanks,

-jane

[m Ransley]

Why not get the builder to fix it, isnt it under warranty. I can only think of improper dampening - bumpers. Although someone else here will know more of the cause.

[Speedy Jim]

Sounds like expansion/contraction issue. The Hot supply pipe expands and has to move lengthwise. Has to move back as it cools. If the pipe goes thru a very tight hole in a joist, for example, it can make weird noises as it jerks.

Probably gonna be tough to fix and the builder will blow you off. "Oh...it'll wear in..."

Anyway, that's my theory.

Jim

[George E. Cawthon]