Exterior of Bella Bella Passive House/ Source: Metric Modular
The project consisted of six, two-story attached townhomes to be used as
a desperately needed housing solution for Yale First Nation. Each module
was prefabricated at Metric Modular’s Agassiz facility and the modules were
approximately 32 feet long and 14 feet wide. After bad experiences with
previous onsite builders cutting corners and building poor quality homes, we
were able to provide six high-quality housing units for the community. The
design of the building allowed each tenant to have a private outdoor space,
while still maintaining the feeling of community. As a Passive House, the building
was specifically placed on site to take advantage of solar gains and area views.
To meet rigid Passive House standards, each module
- • Efficient building shape – using a ratio known as the
‘Shape Factor’ (the ratio of the buildings surface area
divided by its volume) the heat loss from a building
envelope is minimized.
- • Superinsulation – incorporation of the correct levels
of insulation performance depending on the climate
- • Advanced windows – using triple glazed units, with
two low-e coatings, argon gas fill and insulated frames
- • Airtightness – prevention of air infiltration and
protection against moisture damage.
- • Thermal bridge-free construction – preventing an area
of the building which has a significantly higher heat
transfer than the surrounding materials, resulting in an
overall reduction in thermal insulation of the building.
Passive House standards reduce energy costs by up
to 80 percent, drastically increase occupant comfort
and reduce the GHG emissions of the building by 80
percent during occupancy.
Blueprints of Bella Bella Passive House / Source: Metric Modular
As this was our second Passive House project, we were
able to save our customer money through the experience
we gained during the previous project. We also utilized
the three Certified Passive House Consultants on staff
rather than hiring expensive outside consultants. Our
experienced design, production and site teams were able
to prevent building envelope issues before the modules
arrived onsite. We were able to reduce the number of
pre-tests and consultants’ visits, while still achieving
an above average building envelope airtightness test
Interior of Bella Bella Passive House / Source: Metric Modular
We completed most of the roof construction offsite
in order to reduce site work, preinstalling the exterior
building envelope (siding), and pre-fabricating porch
elements. Previous winter energy bills for the Yale First
Nation were in excess of $250 for one month. The energy
bill they received after over a month of occupancy was
under $20. This on-going savings will make drastic and
lasting impact to the economics of this community.
This article originally appeared in the Modular Advantage Magazine - Fourth Quarter 2018 released in November 2018.