Plumbing insulation
dfvellone
| Posted in Mechanicals on
I’m installing a new home-run plumbing system and will be insulating all the 1/2” pex tubing. Armacell offers a continuous coil of insulating sleeve (non-slit). I’d prefer the continuous sleeve that has no slit, but wonder if installing in long lengths may have challenges that I’m not seeing.
Thanks, Daniel
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Replies
It can be less than fun to put on the sleeve to begin with, you won't be able to pull it through holes in joists, and you'll have to cut out chunks of the sleeve at each fitting and support strap. Aside from that, not a big deal. The biggest issue I can see is running the pipe through holes in framing, so you should plan your insulating job around that (i.e. don't insulate lengths that are longer than you can use as an single insulated section of pipe). You can always add some of the slit-type insulation in any tricky spots and use the continuous stuff for the longer runs.
Bill
The majority of the runs are in a chase, or in a rafter bay, and I’ll have plenty of armacell for all of the hot water lines, and I can isolate the cold lines easily and wonder if I can pack rock wool around them to prevent condensation or, if as in my partition walls insulated roxul safe n sound, they may still be subject to sweating.
Rock wool isn't a good option if your concern is sweating pipes, since moisture could still get to the cold surface of the pipe and condense.
Bill
Daniel,
I like the slit. Much easier to work with, or temporarily remove. The heat loss through it is in the weeds.
It seems that it would just take a bit longer for the water to reach ambient in the pipe. https://www.greenbuildingadvisor.com/question/heat-pump-water-heater-for-a-hydro-air-system-w-integrated-hrv Run 3
Uponor offers pre-insulated PEX-A if you want to avoid the slit.
I've wondered how effective pipe insulation is for faucets that aren't used constantly. It seems that it would just take a bit longer for the water to reach ambient in the pipe. Be effective for noise reduction though.
AC200,
Even thought I live in a temperate climate, some heat is welcome nine months of they year, so I don't really care about standby or pipe losses. The only use I see for pipe insulation is stopping condensation.
Pipe insulation does a lot for copper pipes but for PEX or other plastic pipes it's kind of overkill. Traditionally it has uses for both cold and hot water lines.
Insulating cold water lines prevents condensation.
Insulating hot water lines saves heating energy (kinda meh), but also keeps the temperature more steady and potentially gets you hot water faster, which is a noticeable QOL on long copper runs with a standard pressure-balance shower.
Pipe insulation does just as well with PEX as it does for copper. The very thin (relatively) wall of PEX pipe does not appreciably change the amount of heat lost through the pipe compared to copper. Hot water lines should ALWAYS be insulated. Cold water lines can be insulated if you find you have condensation issues.
Bill
I'm also interested in your experience with Armacell's continuous coil insulation for your home-run plumbing system! While the convenience of a non-slit sleeve sounds appealing, I share your concern about potential installation challenges in long runs.
Armacell continuous coil insulation:
Armacell website: http://www.armacell.com/
Product page: https://www.armacell.us/products/aparmaflextubes/ basket random