Rossland Passive House

Rossland, British Columbia, Canada

#Passive House #Low Embodied Energy #Healthy #Cold Climate #Solar PV

The Tan Kok Passive House in Rossland, BC reaches new heights for energy efficiency in cold climates. The modest footprint drives efficiency in not only space planning but performance. In the first year total cost of energy for this home was remarkably only $200.

This house was designed to use almost no foam. Instead most of the insulation uses cellulose which results in lower embodied energy and less off-gassing. The whole shell was prefabricated off site and assembled in four days. To make sure it met Passive House stringent 0.6 Air Changes Per Hour (ACH) air tightness criteria, it was tested for air leakage after assembly. The final tightness was a remarkable 0.285 ACH. Once the shell was installed without even windows or heating source in November, the trades were wearing t-shirts allowing them to work more comfortably and efficiently.

The house has drain water heat recovery, beautiful Wooden Passive House windows, and can generate all the electricity it needs on clear summer days with a 2.4 kW solar PV system that also provides shading to the windows below keeping the house cool in the summer.

The Specs

Treated Floor Area according to PHPP

141.1 sm (1,518.7 sf)

Construction Type - wood framed

Year of Construction - 2015

Team

Designer - Brett Sichello Design - Passive House Designer and Energy Modeling Consultant
Structural - MacLeod Nine Engineering
Mechanical - Hydraft Development
Builder - Seven Summits Contracting
Prefabricator - Collective Carpentry - Thermal Envelope Fabrication and Assembly

Thermal Envelope

Exterior Wall - Effective U-Value 0.095 W/(m2k) - R60

12.7mm 1/2" Gypsum Board - 0.025 W/(mK)
140mm 2x6" Wood Studs @ 24" o.c with R22 Fibreglass Batt Insulation - 0.037 W/(mK) 7% framing
15mm 19/32" OSB - Airtight Layer (all seams taped and sealed with SIGA or Proclima tapes - 0.013 W/(mK)
285mm 2x12" @ 24" o.c. with Densepack Cellulose Insulation - 0.038 W/(mK) 10.4% framing
16mm Agepan DWD Fibreboard - 0.045 W/(mK)

Suspended Floor over Garage - Effective U-Value 0.070 W(m2K) - R81

16mm 5/8" Bamboo Flooring - 0.18 W/(mK)
19mm 3/4" Plywood Decking - 0.13 W/(mK)
140mm 2x6" Wood Studs @ 16" o.c. with R22 Fibreglass Batt Insulation - 0.037 W/(mK) 10% framing
15mm 19/32" OSB - Airtight Layer (all seams taped and sealed with SIGA or Proclima tapes - 0.013 W/(mK)
406mm 16" Engineered I-Joist @ 24" o.c. with Densepack Cellulose Insulation - 0.038 W/(mK) 4% framing
16mm Agepan DWD Fibreboard - 0.045 W/(mK)

Garage on main level includes a storage and mechanical room which are conditioned as required with small electric heaters. The foundation walls are furred out wit 2x4" wood studs, R14 Fibreglass Batt Insulation, Certainteed Membrain, 1/2" Gypsum Board. The concrete slab is uninsulated which allowed this house to be 99% foam free construction. The only elements in the entire home which include foam insulation include two steel entry doors in entry stairwell which is outside of the thermal envelope and within the steel faced insulated garage door.

Roof - Effective U-Value 0.061 W(m2K) - R93

12.7mm 1/2" Gypsum Board - 0.025 W/(mK)
140mm 2x6" Wood Studs @ 24" o.c with R22 Fibreglass Batt Insulation - 0.037 W/(mK) 8% framing
15mm 19/32" OSB - Airtight Layer (all seams taped and sealed with SIGA or Proclima tapes - 0.013 W/(mK)
406mm 16" Engineered I-Joist @ 19.2" o.c. with Densepack Cellulose Insulation - 0.038 W/(mK) 4% framing
89mm 2x4" Wood Studs cross strapped over I-joists @ 24" o.c with Densepack Cellulose Insulation - 0.038 W/(mK) 4% framing
16mm Agepan DWD Fibreboard - 0.045 W/(mK)

Windows

Frames: Optiwin Alu2Wood Uw = 0.95 W/(m2K)

Glazing:

South and West Elevations - Sanco Silverstar Trille E (4EF-TRE-18AR-4EF-18AR-TRE-4EF)

g-Value - 0.62
Ug-Value - 0.60 W/(m2K)

North and East Elevations - Sanco Silverstar EN2PLUS (4-18AR-4-18AR-4)

g-Value - 0.53
Ug-Value - 0.50 W/(m2K)

Entry and Balcony Doors are also Alu2Wood windows with integrated door hardware

Mechanical Systems Ventilation

Zehnder Comfoair 200 - Heat Recovery Efficiency 89.4%

Heating and Cooling

Radiant Exergy Heating and Cooling system with pex tubing running from two buffer tanks connected to the the heat pump which distributes the energy to aluminum plates secured to the underside of the second floor framing and roof service channel framing. An additional pex line runs from the buffer tanks to a heat exchanger in between the HRV and main supply air distribution box to heat/cool the ventilation air. When cooling, the lines can not be ran below 18 C or condensation could occur however this is more than cool on even the hottest of days.

Domestic Hot Water: Natural gas hot water tank.
Drain Water Heat Recovery: supplements up to 30% of the total water heating requirements.

PHPP Values

Air Tightness: n50 = 0.285 ACH
Annual Heating Demand: 12.99 kWh/(m2a)
Heating Load: 12.11 W/m2
Primary Energy Requirement: 97 kWh/(m2a) - to be verified