Friday, January 22, 2010

What LEED needs to become to become relevant

THE PASSIVHAUS VS. THE SOLAR HOME
Tree Hugger - It is hard to believe, but this "mountain hut" in Austria needs next to no heating; it is all done with body heat, cooking heat and passive solar heat. it is an example of a Passivhaus design, built to a standard developed by the Passivhaus Institut in Germany, based on the work of Dr. Wolfgang Feist.

Green Builiding Advisor - An energy-efficient house without solar equipment. Designed by architect Christoph Schulte, this superinsulated home was the first Passivhaus building in Bremen, Germany.

More and more designers of high-performance homes are buzzing about a superinsulation standard developed in Germany, the Passivhaus standard. The standard has been promoted for over a decade by the Passivhaus Institut, a private research and consulting center in Darmstadt, Germany. . .

The Passivhaus standard is a residential construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor

Unlike most U.S. standards for energy-efficient homes, the Passivhaus standard governs not just heating and cooling energy, but overall building energy use, including base load electricity use and energy used for domestic hot water. . .

Although the Passivhaus Institut recommends that window area and orientation be optimized for passive solar gain, the institute's engineers have concluded, based on computer modeling and field monitoring, that passive solar details are far less important than airtightness and insulation R-value. . .

In Europe, most homes are heated with a boiler connected to a hydronic distribution system. Since residential forced-air heating systems are almost unknown in Europe, many Passivhaus advocates declare that their houses "have no need for a conventional heating system"ˇ - a statement that reflects the European view that forced-air heat distribution systems are "unconventional."ˇ