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Re: GSBN:HRVs and SB

>so that if you can show that a given design will meet the
>overall intention of the code with the use of exhaust-only
>ventilation (bathroom fans with timers) rather than an HRV, I would
>imagine that you would be OK.

Hello Paul and all those who responded to the HRV question:

Thanks for all the answers and advice! I think perhaps I wasn't clear on
what I was looking for, but Paul kind of hit on it above. I'm not against
HRVs, and understand their benefits. What I was hoping to find was an
alternative to the expensive, off-the-shelf units that are a constant draw
on an off-grid energy system. I was thinking that there must be passive
and/or non-electric active means of providing fresh air in a home.

The system I suggested to our local inspector for my brother's home would
use a pair of 2 inch ducts from outside which enter the house as part of
the masonry shroud around his woodstove, plotting a "circular" course
through the masonry and opening into the house directly below the stove.
This path through the warm mass of the shroud, I figgered, in my
non-scientific figgering way, would warm the incoming air, while the
circular pattern would prevent a convection loop from happening when the
stove is cold. A small, low-draw fan in the upstairs bathroom would provide
exhaust. This figgering came from experience at my own home (where all
sorts of hairbrained schemes are hatched and occasionally raised into
semi-feasible ideas), where the fresh air intake is a garden hose that
enters from outside, is coiled in the very warm ceiling over the woodstove,
and then feeds just behind the stove. This works passively, which I needed
since there was no electricity of any sort in the house for a long time
(the diameter of the hose is nowhere near what it should be, but it's
undersized nature is what made me think that kick-ass HRVs with miles of
ductwork might be overkill).

Any time we suggest any sort of set up like this to an inspector (we've
built a similar system, but with the intake coming through a heated slab,
in the pre-HRV-is-the-law days), we get told we need to "prove it". I was
hoping some GSBNers would have "proofs", or know of similar systems that
have been "proven". It's not that HRVs don't work, but the cost, the
required ductwork, the power draw and the sheer mechanical nature of the
solution just seems to beg for reasonable alternatives.

So, I'm begging...



Chris Magwood / Camel's Back Straw Bale Construction

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