Wayne Whitney wrote:
On 2008-04-09, dpb wrote:

I ken, but there's also the thermal expansion/contraction which while
not _as_ significant w/ cast as plastic is a potential if the mount is
rigid against the hanger. Different noise, surely.

Another good point. I'll go with the plumber's tape. Thanks for the
help.

No problem...as you may have guessed, I've done very similar before...

One more note on the solidity of the mounting since that seems to be
your concern--I earlier wrote

"... get it in place w/ the tape it will be every bit as stout as you
could wish, particularly if you on occasion wrap it 360 around rather
than just support it from underneath."

I'll note that since you have access to the joists, one way to
accomplish this is to occasionally where you wrap the tape around to
fasten one end solidly, then use a lag or even a bolt through the other
end and use that to tension the tape--it'll make a solid mount that
still has a little flex. Even though the tape is tightly wound against
the pipe, that it isn't rigid means it will move slightly w/ the pipe
instead of any inclination of there to be a noise problem w/ a more
solid mount.

HTH...

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