Replies

1. 
   BoJangles | Aug 12, 2008 02:59am | #1

   I know what you mean, but nobody I know ever uses them.  I have about 1000 of them in different sizes in the shop.

   You can buy them at any real plumbing supply outlet.  They are commonly referred to as bushings, just like you said.

   They come in various sizes.  They are usually long enough to use with regular 2x lumber.  You would want a 1 1/2" OD to push into the standard hole in an I joist.

   They have rings on the outside, like a ring shank nail.  They are made out of plastic. 

   They can reduce noise from pipe movement in a hole...but so can a properly sized hole without one.

   They aren't real expensive, so if you feel better using them, find the plumbing supply outlet that the real plumbers or heating guys use.

1. 
   rockarau | Aug 12, 2008 03:48am | #3

   If  I do not  use bushings , what size hole  for  3/4 PEX ?

1. 
   BoJangles | Aug 12, 2008 02:36pm | #4

   Most tradesmen just use the knockout holes in the I joists.  You will probably have to drill new holes in places to get them to align.

   It's important to make sure the piping is routed so it has room for expansion movement and not bent sharply near the holes.  If it is just loosely strung through the holes, I haven't encountered any noise problems using Pex.  If you are running heating lines, make sure you orient the lines properly at the ends of the joist bays.  They should loop and run from the far side of the joist bay and in to the hole to pass through into the next bay.

   Copper can really be noisy if it allowed to rub on the sides of a hole in a joist.  I'm talking about heating applications mainly causing this problem.

1. 
   rockarau | Aug 15, 2008 04:24am | #10

   I saw the bushings I mentioned in an issue of FHB. I believe it was Issue #153, but I am unable to locate my copy. I am trying to find out the contents of the article, as I recall that they were specific to I Joists.

2. 
   FatRoman | Aug 12, 2008 03:14am | #2

   See if this is what you are looking for
   http://www.pexsupply.com/categories.asp?cID=859&brandid=

   'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
3. 
   jej | Aug 12, 2008 09:31pm | #5

   the item you want is a plastic insert and you drill a 1 3/8 hole

1. 
   marv | Aug 12, 2008 11:00pm | #6

   Souix Chief sells a plastic insert.  Drill a 1 3/8 hole for 1/2 or 3/4 pex and insert.  works great. I use them in every stud.You get out of life what you put into it......minus taxes.

   Marv

1. 
   MSA1 | Aug 12, 2008 11:13pm | #7

   Is there really gonna be enough friction to necessitate bushings for pex?

   I know they make the bushings, but they also made the Chevy Geo. 

    

    

   Family.....They're always there when they need you.

1. 
   marv | Aug 13, 2008 04:22pm | #8

   Thats the way I was taught to do it by a plumber I trust...so thats the way I do it.  He also likes to fasten it every 12".  Maybe its overkill, but I follow his lead.You get out of life what you put into it......minus taxes.

   Marv

1. 
   MSA1 | Aug 13, 2008 04:26pm | #9

   Nothing wrong with overkill. Just wondering. 

    

    

   Family.....They're always there when they need you.

4. 
   Bing187 | Aug 15, 2008 04:54am | #11

       My plumber puts a short piece ( like 1" ) of pipe insulation around pex where it goes thru I joist or subfloor. Never had an expansion noise issue

   Bing