While the Passive House building standard has grown to become recognized by architects and building professionals worldwide, there is another building standard that takes a similar approach and amplifies it further.
Active House, although less commonly known, is a building standard concept believed to be first established in Denmark. But what is Active House and how does it differ from Passive House and other green building programs and approaches? According to the Active House website, the Active House approach is:
a vision of buildings that create healthier and more comfortable lives for their occupants with negative impact on the climate – moving us towards a cleaner, healthier and safer world.
While this statement is high level and visionary, Toronto-based green building specialist Matthew Sachs helps clarify the Active House approach a little further. On his blog “Inside the Energy Evolution”, Matthew notes that the Active House approach takes many of the same concepts of Passive House such as superinsulation, air tightness and maximizing solar and amplifies it. In the Active House approach there is a greater focus on natural light and ventilation.
The Active House approach has three main criteria as outlined by the Active House website.
- Energy – There is a positive contribution to the energy balance of the building. All energy is supplied through renewable energy sources that have been integrated into the building or from a nearby energy system and electricity grid.
- Indoor Climate – The building creates a healthier and comfortable life for building occupants by ensuring there is a generous supply of natural sunlight and fresh air. Furthermore, the materials used in the construction of the building have a neutral impact on the environment.
- Environment – There is a neutral impact on the environment. The building interacts with the environment through an optimised relationship with the local context, focused use of resources, and its overall environmental impact throughout its life cycle.
How does Active House differ to Passive House?
Aside from the aforementioned increased focus on natural sunlight and ventilation, there are some things to consider. Passive House tends to have a primary focus on energy efficiency while the Active House approach expands the focus on quality of life (which is where indoor air quality, fresh air and natural sunlight considerations come into play).
Toronto-based green building specialist, Matthew Sachs notes in his blog that both Passive House and Active House approaches rely heavily the orientation of the building to maximize solar which means the building needs to be set south facing.
Active House buildings tend to feature additional windows. While that typically means that less insulation is used to insulate the building, the use of a “superinsulation” can still contribute and help optimize the performance of the building itself. In the same way spray foam insulation can help a building meet Passive House standards, spray foam insulation can also help a building meet Active House standards.
Active House in North America
The world’s first certified Active House was built in Toronto by local builder Great Gulf. The home feature technologies including skylights, a home monitoring system, a three-zone furnace and heat pump HVAC system and engineered wood sheathing panels. The home itself is a living example of an Active House with a family of five living and monitoring the performance of the home.