ecoHouse 4 - Bernhardt House - Contractor’s interest in high performance begins at home

- Collaboration in design and construction that enables the built environment to be comfortable and attractive while also being affordable and sustainable.

- Exceptional energy efficiency without  a green cost premium.

- Thoughtful design and careful construction so the buildings of tomorrow are vastly better than those of the past.

The above are the tenants of the partners of the Bernhardt Passive Home.

By Rob Bernhardt

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”What if we got serious about energy conservation, and instead of aiming at 30% savings for one house on the block, aim at 90% savings, while making it affordable to all?”

- Wolfgang Feist, originator of the Passive House Standard

The Bernhardt Passive Home, a project of Victoria’s Bernhardt Contracting, seeks to improve the built environment by demonstrating:

- High-performance buildings pay.
- With thought and care, high-performance construction is widely achievable.
- The most important aspects of building energy efficiency are basic design and construction principles.
- Proven performance increases building market values.

Greg Damant of Cascadia Architects in Victoria is the architect of the two-family, 4,000sf residence designed with a flexibility in layout to meet various housing needs. Compared to most passive house designs, this project has a relatively complex form due to the lot shape and orientation, the program and zoning requirements.

Budget and Cost Details

Most of the components of a passive house are those used in conventional construction. The cost differences arise from an increase in the cost of design, insulation, framing, doors and windows, and a higher quality HRV.  Although the increased wall thickness costs more, the efficient form of a passive house envelope can be less expensive than the complicated envelopes commonly seen in Canada due to the reduced wall area and elimination of corners and junctions.
Mechanical costs in a passive house are significantly less than in conventional construction. To replicate the thermal comfort of a passive house, most homes require a high-quality heating system in the floors and under windows. An HRV is still required to ensure air quality, although a less efficient model is adequate for conventional construction.
Even with the reduced mechanical costs, passive design is usually slightly more expensive overall, but if the incremental cost is added to a mortgage, the energy and maintenance savings make the residence immediately cheaper to live in, without waiting for a payback period.

Does Passive House construction cost more?  Depends. There are many factors and ways of looking at the issue. Whatever method of analysis is used, it is clear Passive House is affordable and, in almost all cases, cheaper to own and operate than conventional construction of comparable quality.

MATERIALS

PROJCT CREDITS

  • Architect Cascadia Architects
  • General Contractor Bernhardt Contracting Ltd.
  • Passive House planning & energy modelling Rob Bernhardt
  • Wall panels, trusses, joists & beams Victoria Truss Ltd.
  • Plumbing & Mechanical City Service Plumbing & Heating Ltd.
  • Photos Derek Ford

PROJECT PERFORMANCE

  • - PHPP specific space heating demand = 10 kWh/[m2a]
  • - PHPP Heating Load = 11 W/m2
  • - Air tightness  = 0.5 ACH @ 50 Pa
  • - PHPP specific primary energy demand = 81 kWh/[m2a]

Rob Bernhardt, BCom JD is a project manager at  Bernhardt Contracting Ltd. in Victoria.

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