The Passivhaus Institut Building Standard limits the amount of heating and cooling energy required to maintain indoor comfort based on a building's square footage. For new construction, it's 4.75 kBTU per square foot per year. For renovations, it's 7.92 kBTU per square foot per year. To maintain indoor comfort with such a small amount of energy, the building must be insulated sufficiently and made sufficiently air tight. The specific climate zone and the building's specific GPS coordinates and site orientation dictate the amount of required insulation. The airtightness requirement is ".60 ACH at PASCAL 50" for new construction and "1.00 ACH at PASCAL 50" for renovations pursuant to a third party instrument measured proceedure. PASCAL 50 represents a pressure standard approximating a constant 20 MPH wind. To achieve these two non-negotiable limits great attention must be paid to the "building envelope."
When you own or reside in a Passivhaus Institut Certified Building you know what to expect - negligible energy expense, pristine air quality, no drafts, acoustical separation, tight temperature and relative humidity dispersion 24 x 7 x 365. This leads to a > 90% reduction in heating and cooling expense, > 90% reduction in dust, pollen, mold and airborne bacteria and a 90% reduction carbon emissions.