Pile foundation and Passive House – Example Fort St. John affordable housing project
Close to completion, this 6 storey and 50 unit apartment building located in Fort St. John is slated to become one of Canada’s largest certified Passive House Buildings.
It is also a first worldwide, as it will be the Northernmost multi-storey Multifamily Building to meet the stringent international Passive House Standard.
This collaboration project between BC Hydro and BC Housing is scheduled for occupancy in early 2019 and will be home to some BC Hydro workers and their families and provide affordable rental housing to the community.
BC Housing is leading the development, construction, management and operation of the building. Later this year, BC Housing will seek a non-profit building operator through a public contracting process. The building operator and BC Housing will share information regarding eligibility and how to apply for the affordable housing units.
This project had many design challenges to overcome mainly related to the frigid winter temperatures of up to -40 degrees celsius and a site where the soil was not structurally sound to build such a large building on.
Because of that the foundation proposed is sitting on over 200 steel piles with concrete beams to accommodate the slab, which brought on quite some challenges to the design team.
Knowing that wrapping the foundation in continuous rigid insulation would be ideal to mitigate potential thermal bridges that could negatively impact the overall performance of the building, the team was looking at different options to apply an efficient and cost effective thermal break.
Having looked at different thermal break products from Europe and the US (including Schoeck or Farrat) and different rigid insulation applications and modelling connection detail variations extensively in THERM, the selected solution ended up to focus on wrapping the steel piles, connections points and grade beams in rigid insulation, at the end resulting in an acceptable thermal bridge ranging from 0.15 to 0.65 W(mK) and adding approximately 2 Kwh/m2/yr to the heat demand of the building.
More construction images and updates on the project can be found here: Https://markendc.com/multifamily-passive-house-bc-canada.html
Marken Design + Consulting is acting as the certified Passive House Consultant and certification coordinator on this groundbreaking project.