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What type of pipe insulation? Exterior light well domestic hot water.

severaltypesofnerd | Posted in General Questions on

These pipes had 1″ of good old asbestos jacketing, now removed.  What would work best to replace the asbestos?  What type of contractor could do a good job installing it?


The pipes are copper, located in an external three story light well, and heated by a 24/7 running recirculation pump from a basement tank. 

The light well has a roof, making it a semi-dry spot, semi-protected from UV light.

The building used to have steam heat, but this is not steam, it’s domestic hot water for 18 student housing units.   Located in Berkeley CA, Zone 3.

On cost I might say fiberglass with PVC jacket, but given the difficulty of installation I’d be worried about flaws leading to water intrusion.

I’m not OK with regular foam from the Big Orange Store: I know that won’t last or work well.

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  1. Expert Member
    1. severaltypesofnerd | | #2

      I'm just concerned about this not quite dry, not quite UV protected location. My ideal might be some great fiberglass with seam taped PVC:

      But I also know the crew will have to do it in a narrow exterior lightwell with hardly room to turn around.

      The K-Flex is good stuff

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