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Installing HRV, cathedral ceilings and no basement?

Islander6 | Posted in Energy Efficiency and Durability on

Hi im building a very airtight home with 4 inches exterior insulation. The home will be slab on grade and will have vaulted cathedral ceilings. I have no where to install my hrv and ductwork!

Any suggestions?

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  1. gawdzira | | #1

    1. What does the floor plan look like?
    2. What kind of HRV? Zehnder?
    3. What climate zone? (possibly run duct work under slab?)
    4. Is the design locked at this point?

  2. Islander6 | | #2

    Havent picked a type of HRV. House is 3100sqft, very open concept. Design is locked pretty solid at this point. Location is vancouver island so our climate zone is 5 in canada.

    Other option was to drop a fake ceiling somehow and run some ducting, but that feels like a of work and i have no experience duct work in slabs

    1. Expert Member
      MALCOLM TAYLOR | | #5

      User ...076,

      The design is not "locked pretty solid" if it doesn't include provisions for elements like ventilation, seismic bracing or anything else required by code. Before that it's just a concept.

  3. Expert Member
    Akos | | #3

    Hi there (a name works much better than user-7503076)

    HRV can be installed anywhere, since most connections are to bedrooms, shomwhere near them. Good spot is the utility room especially if it has an outside wall. You can also install it in the ceiling of the bathroom (you'll have to drop the ceiling by 8" or so) or a larger closet.

    Ventilation ducting is pretty small, you can run a fair bit of it inside interior walls, the rest would have to be a bulkhead. Depending on the number of bedrooms, you are probably looking at a 150CFM HRV, which means 7" supply and return trunks which you can easily hide in a bulkhead above doors.

    1. Islander6 | | #6

      thank you, yes most of the bathrooms will have drop ceilings and bulkheads in the kitchen. This should suffice for venting with potential a lunos fan in the common area to keep exterior penetrations to a minimum

  4. Expert Member
    Peter Engle | | #4

    Most cathedral houses have some flat ceilings, or can be designed to have areas with flat ceilings. A core of bathrooms and closets can often be created with flat ceilings, giving enough attic space to install an HRV, and ductwork access to supplies in the bedrooms and exhaust from baths (and kitchen, if possible).

    You can also look into Lunos fans. These fans mount through the wall and work by alternating intake and exhaust through a heat exchange core. No ductwork required, but more penetrations in the exterior envelope. Each space requiring ventilation would get its own fan.

    1. Islander6 | | #7

      Thanks peter, any downside to having the lunos fans, any issues with making them air-tight. I plan on making the building extremely airtight and considering putting 1-2 of these fans in main areas along with hrv ducting in bathrooms and utility room which is on a exterior wall which is good

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