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Sustainability is about ecology, economy and equity.- Ralph Bicknese

Homebound Passivity


passveImagine watching a silent movie in color and you might get a sense for what it would be like to watch the world go by from inside a passive house, a super-insulated and energy efficient home that renders any outside noise completely inaudible, also keeping the air incredibly fresh and the temperature a comfortable 70-74 degrees year-round, all while using a fraction of the energy consumed by the average house.

The passive house design achieves these feats by being so airtight (12 to 14 inch thick walls are typical for the Northwest climate) that warm air doesn’t escape during winter and cool air doesn’t in the summer. Sans furnace and air conditioner, mechanisms unique to passive houses (like heat-recovery ventilators) are used to exchange indoor and outdoor air without altering the internal temperature. Vents are placed throughout the house to exchange fresh air, preventing mold.

Apparently, almost 30,000 passive houses have already been built in Europe, a less impressive number of 90 certified in the U.S. The cost of building them is one imposing factor, the complexities involved in the making of something so insulated driving up the price of their construction. Adding to the difficulties of this are the benchmarks a passive house must meet to be certified, and the consequences encountered if it isn’t. First it must past the test of being airtight, then it must not exceed a certain level of heating and cooling usage, in addition to other uses of energy. If these standards are not met, the passive house owner could be hit with thousands of dollars in fees.

Supporters of the passive movement (how often does a sentence like that make sense?) say that the excess cost will come down once more American manufacturers get on the bandwagon, and there are a few positive trends that may signal the fulfillment of their hope. Over 1,000 architects in the U.S. are now passive-house trained, and at least 60 passive-house projects are currently in production.

There may be more hope for us Northwesterners when it comes to the passive house movement. More than a third of the passive houses in the U.S. exist in the Northwest, largely due to the relatively temperate winters and summers, which reduce the complexities of keeping the house at a comfy temperature. The more humid and frigid climates found elsewhere in the U.S. raise greater difficulties. Nevertheless, it seems that the enormous energy savings of a passive house make it an idea worth pursuing. If you’d be interested in touring a passive house, here’s one that’s going to be featured during the explore design home tour on September 14.

Feel free to share your, well, passive enthusiasm below.

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