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Zacblodget

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!

Bruteforceblog

Yikes...

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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