PHnw Building Directory

Aamodt Passive House

Building Use: Detached single-family residence

Project Type: New passive house building

3 bedroom, 2 bath, single level house with attached 4 car garage

Location:Carnation, Washington 98014
Dwelling Units:1
PH Calculation Protocol(s):PHI
PH Modeling Software(s):PHPP
PH Certification(s):PHIUS
Year Of Construction:2016

Project Size

Floor Area:1,340.0 ft2TFA124.5 m2TFA


Annual heat demand:4.64 kBtu/yr•ft2TFA14.6 kWh/yr•m2TFA
Heat load:3.60 Btu/hr•ft2TFA11.4 W/m2TFA
Primary energy demand:37.10 kBtu/yr•ft2TFA117 kWh/yr•m2TFA
Airtightness:0.47 ACH50


Construction Type:wood
Floor Assembly:3/4" plywood sheathing over 16" TJI's at 16" o.c. with dense-packed cellulose (R-55) and 2" (R-12) foil-faced polyiso rigid insulation (taped for air barrier) on underside of joists
Wall Assembly:Metal siding over Tyvek building wrap over 1/2" CDX plywood sheathing (taped for air barrier) over two rows of 2x4 studs at 24" o.c. with 5" gap between with 12" (R-41) dense-packed cellulose and 5/8" gypsum wall board (no polyethylene vapor retarder)
Roof Assembly:Metal roofing over underlayment over 5/8" plywood sheathing over 2x wood scissor trusses at 24" o.c. with 2" (R-12) foil faced polyiso rigid insulation (taped for air barrier) and 18" (R-62) dense-packed cellulose with 5/8" gypsum board ceiling
Windows:Cascadia series 325 and 400 fiberglass, triple glazed, Cardinal low E 180/180, U-glazing = 0.13 (imperial), U-frames = 0.19 (imperial), SHGC-glazing = 0.58 (imperial)
Entry Doors:Fiberglass faced with polyurethane foam core, U-value = 0.21 (imperial)


Ventilation system:Zehnder 350 HRV with Zehnder Comfo-tube distribution
Heating/Cooling system:2000w electric resistance duct heater connected to HRV
Domestic hot water system:Solar hot water (40 evacuated tubes total) with a Rheem 80 gallon electric element backup.
Renewables:Grid tied 8.5kW STC photovoltaic system with SMA Sunny Boy inverter. Net-Zero-Energy for 2016 and 2017 (18600 kWh generated > 18570 kWh used).
Other green building systems:8,800 gallon cistern collecting 100% rainwater for indoor potable use (first off grid rainwater harvesting in King County). Low-toxic and recycled content materials, FSC lumber, minimal use of PVC. Of the 8,250 pounds of waste this project generated, 89


Passive House Consultant:George Ostrow (not a CPHC)
Passive House Consultant Certification:PHIUS
Architect:George Ostrow of VELOCIPEDE architects, inc.
Structural Engineer:HSV Engineers, Inc
Mechanical Engineer:Rainwater system: Chris Webb & Associates, Inc.


Additional Information:This project was built by the homeowners over the course of about 5 years.
Project Website:

View Previous Project View Next Project

Back to Project Directory