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Increasing Pipe Insulation Thickness

Hi guys....I'm curious on what effect thicker pipe installation has on the overall system effeciency.

I currently have 1/2" fiberglass insulation on all my mains and pipe runs.  Would there be a measurable improvement by increasing the thickness to 1" or more?

Obviously more is better, but would it be worth it to buy new insulation for the improvement in effeciency?



    JUGHNE Member Posts: 11,061
    1" of fiberglass for steam is thought to be "the best bang for the buck".
    More is better but you approach the point of diminishing returns on your investment. IMO
    Also 2" thickness can run into clearance problems around floor joists and other pipes.
  • AdmiralYoda
    AdmiralYoda Member Posts: 627
    I haven't priced the 1" insulation out yet....but I'm on the fence on tossing the 1/2" stuff for the 1".

    The system will probably work better, but it might take 10 years to recoup the investment.
  • Jamie Hall
    Jamie Hall Member Posts: 23,303
    It's worth remembering with insulation that there are two reasons for it, not just one.

    The first is the obvious one -- less heat lost from the pipes. But, if I may, I would point out that if the pipes are in a heated space, that heat isn't lost -- just delivered in a different place.

    The other is much less obvious: insulation will increase the speed with which steam can fill the pipes, since there will be less condensation on initial fill. This is significant -- but it's likely that 1/2 inch is enough for that.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • ratio
    ratio Member Posts: 3,627
    I don't think I'd pull the old stuff off—not only are you going to double the labor cost, but it's a nasty job! Just add another ½" over the top of what's there now.
  • The Steam Whisperer
    The Steam Whisperer Member Posts: 1,215
    I'd leave the 1/2 inch on and add 1 inch over that. With the 1/2 inch already on you can pretty much cover the fittings with the next layer. The optimum thickness at the knee on the curve is about 1 1/4 inch thick.
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