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It still bugs me that people make the argument that a passive house is too airtight, and its better to rely on sloppy construction and bathroom fans instead. If it gets too stuffy, open a window like you would on any other house!
And to be clear, the SIP panel is only one way of framing a passive house. A double stud wall with dense packed cellulose is another approach that works well, and is both common and easy to build.
And lastly, I think our reliance on "traditional details" has more to do with laziness than their actual effectiveness. It takes time to run a model in WUFI to determine where the dew point occurs in a wall design and whether it will dry properly, but that doesn't mean it shouldn't - or can't - be done. A little bit of extra thought and care by the designer isn't that big of an expense relative to the payoff in energy savings over time.
sorry for the rant!



A few misconceptions worth noting:

Not all Passivhaeuser rely on solar gain for heating – in cooling-dominated climates battling internal heat gains is hard enough, solar gain just increases cooling demand. Additionally, not all Passivhaeuser in heating-dominated climates are able to utilize passive solar gains, and have to rely on minimizing losses (usu. better glazing/more insulation) and maximizing process energy (from internal sources) and supplemental heating.

Not all Passivhaeuser rely on high thermal mass – in fact many don’t have much mass at all, unless you count 5/8” GWB to be high thermal mass. There are some PH designers who do utilize high thermal mass, but those are few and far between.

You can build a Passivhaus with products here in the US, although the window manufacturers are light years behind Europe and don’t seem to be in a hurry to catch up.

The embodied energy and operational energy of a Passivhaus is far below that of the embodied energy + operational energy of a code minimum house (and even most LEED projects). This is because operational energy of a typical building is about a factor 10 greater than embodied energy (and this is before operational energy source factors are calculated).

While there are several Passivhaeuser surrounded w/ petroleum-based foams, it’s hardly an oxymoron. To me, the biggest ‘green’ irony is spending hundreds of hours to reduce the embodied energy of projects by maybe 15-20%, while doing very little to fix the larger issue - curbing operational energy and their subsequent CO2 emissions. Or utilizing HCFC-based spray SPF and calling it ‘green’.

Lastly, there are oodles of Passivhaeuser built of straw, rammed earth, cross laminated timber, clay brick, and wood stud with cellulose – all having significantly lower embodied energy than one with petroleum-based insulation. All of these projects significantly outperform ~95% of LEED projects.

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