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Framing and Insulating Around PEX Plumbing

PLIERS | Posted in General Questions on

So planning on insulating and framing around concrete wall in basement.  Going to use 2inch eps foam with 2×4 framed wall in front.  I have pex lines running behind a pvc 4in sewage drain.  One copper line I want to replace with pex tubing.  So I have a few questions, I attached pictures for better look.

1. Do I need to move pex away from wall and in front of pvc sewage line or can I insulate them in that spot?  If I do move them how do I place them so I can frame the wall?  Do I have to disconnect all water lines, frame and then put them through.

2.  I have to change one copper line with pex because it’s running along a ceiling joist.  Can I simply cut the line at ceiling joist turn it 90 degrees left a few inches then reconnect so it runs straight down wall in new spot away from ceiling joist?  Basically can I turn pex any direction I want or is it more complex than that.  I’m a beginner and don’t want to screw up plumbing.

3. As you can see in pictures concrete is old and worn.  Do I need to restucco these wall before I insulate and frame them?

Thanks for any help, the advice I got on this forum has helped me through some difficult projects.

-Joe

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Replies

  1. Ikibbe | | #1

    Hey Joe,

    Hopefully you got this figured out. I’m in a similar situation and curious about what you ended up doing. Was planning on running PEX near some drain pipes and need to insulte them. Was thinking of spray foam for that area, but not sure. Thanks!

  2. PLIERS | | #2

    I have a plumber coming to move all my pex tubing so most of it runs in front of and along drain line. This way I can insulate walls and box in the sewer line with the pex tubing. It is possible to move pex yourself, not sure good you are with plumbing, I opted to have someone do it. You could slip insulation behind drain pipe if there is a gap or I guess push rigid foam as close to sewage line and then use spray foam to seal gap. Hope this helps, Joe

  3. Expert Member
    BILL WICHERS | | #3

    1- You can generally insulate the lines in place, but if this is a wall that might see freezing temperatures, then I'd relocate the lines to the inside face of the insulation. You don't want the pipes to freeze, and putting insulation between the pipes and the conditioned interior space will make the pipes colder, and thus more prone to freezing.

    2- I don't see a problem with moving the line the way you descibe. Just make sure the line is placed so that it's unlikely to be nailed into during some future project. Use nail plates as required for protection.

    3- I've never worked with stucco so can't really offer much help with this one.

    Bill

  4. PLIERS | | #4

    Update: so I moved all the pex lines forward off the wall. I can now insulate as much as I can behind the drain line, might only be 1/2 or less rigid board. This leaves a gap along the top of the wall between joists and drain pipe. The drain line is close to joist but not touching (picture attached). Do I shove pieces of rigid foam in between top of drain line and joists? Can I spray all around the plumbing with spray foam to close gaps? Basically spray foam won’t damage plumbing correct

    Also I can get about 2 inches of foam between foundation wall and water lines. Plumber says to wrap everything in pink insulation. Would that actually make the water lines cooler and I should not wrap it? I read above that you should not insulate between pipes and inside room

    1. Expert Member
      BILL WICHERS | | #5

      Spray foam won't hurt the pipes. I'd use spray foam here, and you might find this is a good place to use the tiny 12 board foot kit of 2 part spray foam. If you use that kit, it helps to submerge the cans in a bucket of warm water while you're spraying.

      I would not use fluffy pink insulation here. Use proper pipe wrap insulation. you can get rigid fiberglass split pipe insulation at commercial supply houses that will fit over the larger pipes. You can also get purpose-made insulation fittings to cover the plumbing fittings. You'll get a clean and professional appearance using this stuff, and you won't have to worry about it coming apart over time. Make sure to get some of the matching tape if you get this type of pipe insulation, since you need the tape to assemble the pieces.

      Bill

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