Passive House library

At the Construction Committee meeting on Sunday, there was considerable discussion about the Passive House standard as a guide for the design of the new library. Passive House is a rigorous energy performance standard that originated in Germany in the 1990s. Here's the basics:

Performance Characteristics

• Airtight building shell ≤ 0.6 ACH @ 50 pascal pressure, measured by blower-door test.

• Annual heat requirement ≤ 15 kWh/m2/year (4.75 kBtu/sf/yr)

• Primary Energy ≤ 120 kWh/m2/year (38.1 kBtu/sf/yr)

In addition, the following are recommendations, varying with climate:

• Window u-value ≤ 0.8 W/m2/K

• Ventilation system with heat recovery with ≥ 75% efficiency with low electric consumption @ 0.45 Wh/m3

• Thermal Bridge Free Construction ≤ 0.01 W/mK

This kind of construction is so energy-efficient, the buildings don't need a furnace! The JTEL board and the construction committee are leaning toward this design standard because it will keep operating costs for the building very, very low. Passive House is a performance standard only, however; unlike the LEED standard, the greeness of the materials or whether they are of local manufacture is not a consideration. For more information on the Passive House standard, check out these links:

• detailed information on what makes a building a Passive House
• Passive House Institute of the US
• Swiss Passive House equivalent: the Minergie standard
• Wikipedia entry on Passive House