The payback period for the embodied energy of the incremental construction materials needed to meet the Passivhaus standard is surprisingly short
Images:
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A common PassivhausA residential building construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor. Developed in the early 1990s by Bo Adamson and Wolfgang Feist, the standard is now promoted by the Passivhaus Institut in Darmstadt, Germany. To meet the standard, a home must have an infiltration rate no greater than 0.60 AC/H @ 50 pascals, a maximum annual heating energy use of 15 kWh per square meter (4,755 Btu per square foot), a maximum annual cooling energy use of 15 kWh per square meter (1.39 kWh per square foot), and maximum source energy use for all purposes of 120 kWh per square meter (11.1 kWh per square foot). The standard recommends, but does not require, a maximum design heating load of 10 W per square meter and windows with a maximum U-factor of 0.14. The Passivhaus standard was developed for buildings in central and northern Europe; efforts are underway to clarify the best techniques to achieve the standard for buildings in hot climates. topic that rears its head every now and again is the [embodied energy][4] of construction. While this can be an important issue, we generally feel it's a moot point for Passivhaus projects – especially the ones we design (owing to better optimized assemblies and less insulation!).
[1]: http://www.greenbuildingadvisor.com/sites/default/files/imagecache/blog-river/S-house 2.JPG (Photo of the straw-bale floor assembly of the S-house)
[2]: http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/calculating-embodied-energy-payback-passivhaus-buildings
[3]: http://www.greenbuildingadvisor.com/sites/default/files/imagecache/blog-river/Eliason bar graph.jpg (A bar graph comaring the cumulative primary energy input of various building types)
[4]: http://en.wikipedia.org/wiki/Embodied_energy
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