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Main line pipe insulation

Pin Member Posts: 61
I intend to insulate the main line pipe in the basement and need more info on what kind of insulation I should buy and where I can get it the cheapest.

Should I be using fiberglass or will polyethlyene work also? Is it cheaper to just buy from Home Depot or Lowes or other retailers or online?

Lastly, can someone explain the best way to install the insulation?



  • David Nadle
    David Nadle Member Posts: 624

    Gotta be fiberglass. The foam stuff could melt. HD and Lowes only sell 1/2", not thick enough. Search the Wall for many many threads on this topic.

    I like buyinsulationproducts.com

    Look around for a local supplier though. Insulation is bulky and shipping is expensive.
  • Brad White_204
    Brad White_204 Member Posts: 20

    David has your back on your other questions, stay away from the half-inch stuff, use not less than a full inch but truthfully, most energy codes dictate 1.5" thickness for any steam pipe up to 1.5" pipe size and 2" thickness for larger pipe (up to at least 4" pipe size, should your house be that big...)

    Application is usually "peel and stick" with a longitudinal adhesive lap seam. The joints often have matching tape and the fittings have loose fiberglass "diapers" (I call them) and PVC covers. These are usually sealed with white PVC tape. A brush-on white insulation cement will make it look better, over the tape and any open ends of fibers.

    I have often said that insulation is an easy job to do, but a really hard job to do well.

    When you see a pro's work against your very best work, you will see what I mean.
  • David Nadle
    David Nadle Member Posts: 624

    If you want proof of Brad's maxim you can look at my mains. Uuugly. Learn from my mistakes. Start working in an inconspicuous corner of the basement. Do the near boiler piping last. Your last joint will be a lot prettier than your first.
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