Passive House E-Design

1. The Passive House standard is based on the climates of Europe. Can it be applied to the climate zones in Canada?
Superinsulated houses have a long history in the Canada starting with the "Saskatchewan House", built in Regina in 1978. Dr. Feist has incorporated the findings of those early pioneering examples of superinsulation in his Passive House research and development. It is true that Germany has a more temperate climate than Canada but the Passive House software can be applied in all climates between 40° and 60° that encompasses all of Canada with the exception of the Territories. Passive House buildings have been successfully certified in Minnesota, with its heavy winter heat load requirements. Central Europe enjoys the advantage of building Passive Houses without the need for heating and cooling except for the minimal amount added to the ventilation system. In Canada, we require some additional space heating and added insulation to meet the heating demands in most climate zones.

2. Is the Passive House an experimental concept?
No. The Passive House has scientific and engineering validity as well as tried-and-true practical success. There are currently more than 15,000 Passive House buildings worldwide. The oldest amoung them have been operating since 1991. Many Passive Houses have been monitored and their performance validated. Average overall energy consumption proved to be on the target of 15 kWh per square meter and year [4.754 Btus per square foot and year], and source energy consumption at less than 120 kWh per square meter and year [11.1 kWh per square foot and year]. The European and American successes and experiences serve as a great resource for Passive House design in Canada.

3. Does the Passive House concept limit the design possibilities of the home?
There are no limits for architecture in a Passive House. The design and building materials can be freely chosen. Once a designer becomes familiar with the principles and learns to incorporate these using the Passive House Planning Package software as a design tool, one will be able to do almost anything regarding aesthetics. Practically, there are some design principals that make Passive House easier to achieve such as exposure to southern sun, limiting glazing on the northern side, low surface-to-volume ratio, and efficient location and layout of mechanical systems.

We now desire homes that are energy independent and that are ideally carbon-neutral. The Passive House standard is an opportunity rather than a limitation.

4. How does the cost of Passive House construction compare to that of standard building?
Based on experiences in the US, we can expect that Passive House construction in Canada will require an additional construction investment of 5 - 15%. The added insulation and high performance windows and doors increase the cost while providing reduced operating costs for the future. Downsized mechanical systems and energy savings decrease construction and operating costs. This estimate does not include the use of green building materials or active energy generation onsite such as wind or solar. In general, the high quality of passive construction components tends to be reflected in higher costs. However, it is important to calculate the life-cycle costs of the house incorporating future energy savings to realize the economics of a Passive House.

5. Can the Passive House's air-tight construction lead to moisture or air quality problems?
The Passive House employs an appropriate vapor barrier solution and breathable construction assemblies to insure moisture is not trapped in the building envelope. Moisture in the house is handled by a mechanical, balanced ventilation system with heat recovery, which assures superior air-quality and comfort by continually exchanging the indoor air. Moisture is safely removed, as well as other potentially unhealthy pollutants.

6. Is a Passive House a complicated, high-tech house that is difficult to operate and maintain?
No, the Passive House is focused on the superinsulated building envelope to maintain the passive energy of the house. Without any complex systems used to generate electricity and heat, the mechanical systems are simple and easy to operate and maintain.

7. Can the Passive House Concept be used to retrofit or remodel existing buildings?
Passive House standard can be utilized for existing buildings and has successfully been applied to retrofit projects is Europe. The energy performance standard of the retrofit is lower than the new construction standard due to the existing thermal bridge limitations in the building. As well, the cost of these projects is substantial and may not be justified by the savings at the current energy costs in Canada. In the future, with rising energy prices, Passive House retrofits will likely become more economical.

8. Is a Passive House also a Zero Energy House?
Without adding some type of renewable power generation, the Passive House will require a small amount of external energy to provide the heating and electricity to the house. The Passive House provides an excellent foundation in the move toward Net Zero Energy homes as it remains more cost effective to save energy within the building envelope than it does to generate energy onsite. As costs of wind, solar and other site energy generation technologies are reduced in the future, Passive House can easily move to Zero Energy.

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