We are proud to have designed this Passive House for our local Habitat for Humanity chapter in Corvallis, OR. It is a 3 Bed + 1.5 Bath, 1400sf highly efficient home with estimated utility costs of less than $600/year or less than $50/month. The low utility costs of this house will reduce the owner’s monthly costs, which ensures the long-term affordability of this home. Through a local grant program this house was able to receive a 4.8kw solar PV system which should cover between 50-70% of the total electrical usage of the home.
This home was also designed with low embodied carbon materials, including a Faswall wood-cementious ICF foundation, cellulose insulation, and nearly foam free except for load-bearing thermal breaks. As such, based on BEAM Calculator results combined with OCEC calculations for HVAC embodied carbon accounting, this project contains over 75% less embodied carbon than the same house built using foam based insulation. Not only that, the code-compliant version has about the same amount of embodied carbon as the Passive House version excluding the HVAC system but consumes about 70% more energy per year (EUI of 52 vs 11). This is due to the use of carbon sequestering materials such as cellulose insulation and wood-chip ICF and the elimination of a foam based exterior insulation. In addition, the embodied carbon of the HVAC system for the code house is 30% higher due to needing a larger amount of refrigerant to meet the heating demands. Overall, this means that this highly efficient Passive House has 37% total lower operational and embodied carbon than a code home over a 10 year period, with this gap only widening through the life of the home.
Proud corporate sponsors of this project are: ShelterWorks and SIGA. Project was completed in July 2017