Another Sunny Day at the Whistler Passive House
Last week, I traveled up to Whistler for another site visit to the Rainbow Duplex Passive House and to chat with the Durfeld team, which is always a pleasure. Everything is coming together nicely as the following pictures show – let’s start in the basement/garage:
For this project, we selected the Paul by Zehnder HRV with a 93% efficiency rating. In addition, we have added the Comfofond by Zehnder Subsoil Heat exchanger unit, which is connected to 60 meters of pipe filled with a Glycol-Water brine buried about six feet below grade. This “passively” tempers the incoming air, warming it in winter and cooling it in summer, which ensures that the HRV operates at its most efficient temperature range.
Viessman’s high efficiency Solar Hot Water system with vacuum solar tube panels should provide up to 60% of the hot water demand – one panel for each duplex unit. In addition, a drain water heat recovery system will bring additional hot water energy savings.
The main heating system, when needed, is an Air-to-Air Ductless Mini Split heat pump by Mitsubishi featuring a SEER 26 rating, wide operating range up to -30C, humidity control, 9000 BTU heat output, and I-sensor to pick up cold spots.
The cross laminated timber (CLT) decking on the upper level is still a somewhat novel building system in North America. Manufactured by Structurlam in Penticton, the precision of prefabrication offered a streamlined construction process with reduced waste. The assembly is quite nice looking and therefore can be left exposed. It is also extremely strong, has excellent acoustical properties, and performs well in life cycle assessment studies.
The wires and pipes are neatly tucked away in the 2×4 service wall with Roxul insulation.
This on site mock up shows the full R47 wall assembly, consisting of exterior Cladding, diffusion open, cellulose blow-in insulation, OSB (vapour barrier), AND the interior service wall with Roxul insulation.
If you would like to know more about the details shown above or the project itself, please feel free to contact us: firstname.lastname@example.org