Removing Shower Stall?

[JDHoge]

I agree. That was my original plan, just to "spot stick" the two water lines using tiny bore holes to squirt the foam. The real and future potential damage to the shower wall prompted me to remove the faucet and try to gain access from above.
It seems clear that squirting too much foam would bulge the shower wall. Foam also creates heat as it sets so I was a bit worried about that, too.

[Nursx2]

my 2015 Thor Hurricane 34 J has the exact same problem, going to fix in in the spring when it gets a little warmer!

[JDHoge]

I finished the job today and am posting pictures of some of the work. I used Great Stuff foam and sprayed it on some cardboard to let it harden overnight. Sliced it into strips and inserted them into the shower wall cavity. Haven't tested the results yet as freezing temps are approaching. Will let members know how it works no later than then end of this month when we head south for a camping trip.
Here are the photos. As an after thought it occurred to me that I could have probably used styrofoam peanuts!

[Beacher]

Now you will have rattling pipes AND rattling foam.

[JDHoge]

Beacher,
You may be right, however I stuffed the void fairly well. If I do still have rattling water lines behind that wall, I'm going to pursue the original plan, to squirt Great Stuff foam in very small amounts, up and down the wall, plugging the holes with small aftermarket clear plastic plugs.

[blw2]

Hopefully there will be no need, with your fix.... but if you do, why not instead of drilling, use a length of tubing or pipe as an extension to your great stuff foam can, and target where the foam is going through the same access that you used to take the pictures?

[JDHoge]

Great idea. Thank you!

[Sportfisherman25]

Just a thought , if you take shower valve off the wall could you slide the foam pile insulation that is split down the pipe to muffle sound as well .(pipe insulation you get at home depot)

[JDHoge]

Sportfisherman25,
I think that is a great idea. Much easier than my approach.