PASSIVE SOLAR INDEX

Why participate in the Passive Solar Index?

The most energy-efficient buildings are those designed to harness and retain heat from the sun in the winter, and employ shading techniques to passively keep homes cool in summer. Through the Passive Solar Index program, Ecohome helps designers achieve their performance goals and offers them recognition for their efforts.

Does the world need another home rating system? No, probably not, but this isn't one.

This is a service we provide where building envelopes are optimised to provide a clear sense of how their homes will perform, and where improvements are best made to save money and energy. A typical home in Canada or colder climate zones in the USA will consume over 100 kWh per square meter. To encourage energy efficiency, any home that achieves below 50 kWh will be featured on our PSI pages free of charge, but if you would like to see a Passive Solar home with a Passive Solar Index of only 15 kWh per square meter, take a look at The Edelweiss built by EcoHome here.

Eligible buildings:

The Passive Solar Index applies to all the following:

1. New construction projects with high energy efficiency goals.

2. Renovation projects aiming for very high energy performance with the building envelope.

3. Existing high-performance buildings that have been occupied for at least one year with supporting documentation of energy consumption (all heating bills). Homes that can prove a heat load below 50 kWh will receive retroactive recognition.

Details

The Passive Solar Index (PSI) is a service and recognition system for buildings that achieve a level of energy performance well beyond the requirements of Part 9 of the National Building Code. PSI recognizes the measured performance as well as the consumption forecasts determined by Passive House Planning Package (PHPP), the software program created by the German Passivhaus Institute which is now employed by Passive House organizations internationally.

While Passive House certification requires an energy consumption not exceeding 15 kWh / m² annually, PSI recognizes any building that less than 50 kWh / m² of floor space in heating over a whole year.
Such a performance is a reduction of over 50% compared to the energy consumed by the average single-family home built simply to meet the requirements Canada’s National Building Code.

The PSI scale ranges from 1 to 50 kWh / m² with 0 kWh representing an entirely passively heated home, which to date does not exist as far as we know.
The laws of diminishing returns make it clear that there comes a point where you will simply not see a return on investment when adding additional insulation. PSI exists to help determine the best building envelope specific to individual climates.

PSI case studies

Bergeron - McClure

This country-style single family home is a well-insulated home with a PSI rating of 41 kWh/m².

Edelweiss

With a PSI rating of 15, Edelweiss confirms that comfortable and efficient construction is affordable, and building beyond the requirements of Code is cost-effective.

Kenogami

The Kenogami house in northern Quebec earned a 'House of the Year' award from Green Builder Media and was called the 'Most Resilient House in North America' by the Resilient Design Institute in Vermont.

Documents required for existing projects

Building plans
Details about mechanical systems
Energy bills for a full year

Documents required for new construction

Building plans
Wall assembly details
Details on windows and mechanical systems
Results of a blower door test

Frequently asked questions:

How is the Passive Solar Index different than Passive House?

The Passive House Certification program is a rigorous standard that aims to drastically reduce the heating consumption of buildings. However, this standard obliges the participating project to achieve a level of performance that is very difficult to achieve in unforgiving climates. In particular, the Passive House standard requires a home to have either:

A maximum heating demand of 15 kWh/m2 per year, or
a maximum heating load of 10 W/m2.

Such performance is a phenomenal achievement, but it can often be difficult to justify the investment in materials and labor, as well as the embodied energy that is required to achieve this level of performance. The result of seeking Passive House performance levels can unfortunately have the effect of a increasing the carbon footprint of a construction project in some cases.

In order to encourage designers and builders to create more sustainable and energy-efficient homes, Ecohome believes that the performance standard for green home recognition needs to be broadened. Born of that philosophy is the Passive Solar Index, which acknowledges exemplary homes that do not quite meet that stringent target 15 kWh/m2.

Why is the maximum 50 kWh/m²· per year?

Une maison unifamiliale répondant nominalement au Code de 2012 devrait avoir une consommation énergétique annuelle se situant entre 100 et 150 kWh/m² annuellement. Il a donc été décidé de fixer la performance d’entrée à 50 kWh/m²·an, soit au moins 50% de moins que la performance de la maison moyenne. Cet exploit sera particulièrement aisé à réaliser pour les projets de complexes multi-résidentiels ; avis aux intéressés !

Is this a green building certification program?

No, this is not a green home certification program. Ecohome will issue a certificate to successful candidates recognize the proven performance of your project, but it is not a formal certification. In addition, Ecohome encourages designers and builders who arrive at a design that promises to be below 15 kWh/m2 per year to also seek Passive House Certification.

Can an existing house achieve a PSI rating?

Yes, existing homes can get a PSI rating, but it is a different process. To rate an existing home, we would need the following information - energy bills for at least one year, building plans, technical details of the heating and ventilation system, and the number of occupants during this period.
With the above information, we can determine the average annual heating demand and provide candidates with a home energy consumption rating. This is our preferred route, as it provides a more accurate picture of the necessary operational demand of a home rather than the simulation pathway.

Who can perform the energy modelling?

Anyone familiar with the Passive House Planning Package (PHPP) software can perform the energy modeling, including a member of the project team, but the results would need to be validated by a third party approved by Ecohome. If the energy modeller is approved by Ecohome but is also on the project team, it is still necessary to have the modeling validated by a third party that not part of the project team.

Who decides on the final rating of a home?

The initiative is currently being carried out by Ecohome, however, there are plans to transfer decision-making power to a committee in order to avoid centralizing decision-making.

HOW IT WORKS:

1. Tell us about your project

2. Personalized service

Our engineers will perform an energy simulation based on the documents provided and attribute a Passive solar Index rating on your project.

3. Validating results

After modeling is complete, you will receive a performance report, and any building registering below 50 kWh per square meter can post their project on our case studies page free of charge.