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Community and Q&A

PVC vs. Metal Pipes

CamSustainable | Posted in Energy Efficiency and Durability on

Good morning GBA!
I have been building a house for a while now, taking advantage of most green and uber insulation methods learned here.   I am about to get started with HVAC and wanted to get your opinion/recommendation.
Location near a large lake in norht georgia, have passive air, lots of humidity, have the external pipes wash out system, wanted to know if I can use PVC pipes instead of the metal ones inside the house (due to condensation, as well as being able to wash and flush the the pipes (about 20 feet x 6 runs with total 2 inch drop from one end to the other).
I created a valve system for outside (water drips out but critters can’t go in.
Can I apply inside? I do have heat pump (so is cold and hot air going through the pipes)
Thanks in advance for your response!

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  1. Expert Member
    BILL WICHERS | | #1

    I’m assuming you are asking about your supply lines? Hot and cold water? Modern construction is usually using PEX these days, which is cross linked polyethylene and a very good product. If you did want to use PVC, I’d use CPVC instead, which you have to use for at least the hot water lines if you’re using PVC.

    I personally would use either PEX or copper pipes. Both have their pros and cons, and keep in mind that copper is VERY expensive at the moment.


    1. CamSustainable | | #2

      Hi Bill, I am talking about the air circulating through the house on a PVC pipe versus Metal. So that I clean it. Will the plastic be toxic with hot air in winter? Is it safe?

      1. Expert Member
        BILL WICHERS | | #3

        PVC is commonly used with small high velocity air systems. The biggest issue is the glue, not the pipe itself, in terms of smells. If you use PVC here and want to minimize smell, try to limit how much of the glue oozes into the interior of the pipe during assembly.


        1. CamSustainable | | #6

          Thank you for the reply, it makes sense.

      2. user-2310254 | | #4

        Are you talking about the supply lines for your ERV?

        1. CamSustainable | | #5

          AC, ERV, Dehumidifier/humidifier, Heatpump and exhaust system will all run through the same air ducts. I haven’t figured out each trigger mechanism yet, but the desire is to leverage less pipes and more technology and nature (passive air cooling)

          1. user-2310254 | | #7

            Have you considered having an engineer design your system? You are much more likely to end up with an approach that promotes efficiency and comfort. It's not the kind of thing where you want to cobble together a bunch of equipment and hope for the best.

            Before you go any further, considering reading this article:

  2. Deleted | | #8


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