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Help finding ERV flat roof vent

dubdub1 | Posted in Green Products and Materials on

Much like the title says, I am having trouble finding appropriate flat roof vents for two spot ERV units I am installing. I don’t think I have an issue with the exhaust, as I would think that any roof vent would work. I am having more trouble trying to find a roof vent for a flat roof for the intake side, which as I understand it, would need to not have a gravity damper on it.

Any recommendations would be appreciated. Placement of bathrooms means that there is really only one way to go… Up. Panasonic seems to have an interesting wall vent that both intake and exhaust use, but I haven’t seen something similar for roof.

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  1. user-1135248 | | #1

    You can always rip the gravity damper out of such things, as it's
    usually just a cheap flap of metal.

    It sounds like you need to terminate a pair of vertical ducts above
    the roofline. One way could be to turn 90 degrees and use a wall
    type vent, or even turn 180 with the final opening adequately clear
    of the roof and slap a screen over it. Another option might be
    something like these that I used on my HRV risers -- they're cheap
    and flimsy and needed a bit of modification for the purpose, but
    work well and there are sturdier equivalents on the market too.
    I chose these because the collars had to fit *inside* the pipes
    they sit on and the flanges keep rain out of the joints that
    would otherwise be "reverse flashed".

    How much risk is there of someone kicking it when walking around?


  2. GBA Editor
    Martin Holladay | | #2

    If the type of vent that Hobbit suggested seems too flimsy to you, you can always invest in stainless steel: Stainless Roof Cap Vent for Appliance Exhaust or Intake.

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