Passive House extreme efficiency standards for a solution to climate change.
Efficiency doesn't come from upgrading your 120,000 BTU furnace from 89% efficiency to 97%. It comes from not needing a 120,000 BTU furnace at all.
Climate change is the challenge of our generation. Growing evidence is driving international consensus for action to limit global warming. Buildings consume up to 40% of global energy use and contribute up to 30% of global greenhouse gas emissions – they are a key piece of the puzzle towards a low-carbon future.
During the research phase of Historical Innovations inception a plethora of information was studied to develop an understanding of methods for creating an efficient building envelope. The Passive House Institute has been at the forefront of this research for over 30 years.
Passive House (German: Passivhaus)
•Voluntary standard for energy efficiency. Developed from research into National Research Council Saskatchewan Conservation House (1977).
•Reduces building's ecological footprint. Results in ultra-low energy buildings, requires minimal energy for heating/cooling.
•Standard not confined to residential properties; several office buildings, schools, and commercial units have met the standard.
•Passive design is not an attachment or supplement to architectural design, but a design process that integrates with architectural design. Although it is principally applied to new buildings, it has also been used for refurbishments.
Passive House Canada is leading change in North America
Without doubt one of the most stringent building performance standards found anywhere. Passive Houses are constructed with extreme efficiency as a core principle of design. Passive House buildings consume up to 90 percent less heating and cooling energy than conventional buildings.
- Space heat demand max. 15 kWh/m2a OR heating load max. 10 W/m2
- Pressurization test result at 50 Pa max. 0.6 ACH (both over-pressure and under-pressure)
- Total Primary Energy Demand max. 120 kWh/m2a
The focus on a superior building envelope is the key to establishing a 90 percent reduction in energy usage.
Superior Building Envelope
- No thermal bridging
- Superior insulation
- High performance windows and doors
- Airtight construction, less than 0.6 Air Changes per Hour (blower door test)
- High performance ventilation
- Thermal mass within the building envelope
Building in this manner encompasses a different approach to wall construction. There are many methods of attaining insulation and airtight construction values that meet the stringent demands of Passive House.
Superior insulation within a 6"wood stud wall cavity is difficult to achieve. Recent building code changes have mandated an increase in insulation values that many builders are now addressing with exterior foam insulation; thereby wrapping the building in a warm blanket of protection. While we believe this method is sound thinking, it needs to be approached carefully to reduce the dew point on the sheathing of the structure and it needs to be enough insulation to make a meaningful change. The wall to the left is an excellent example of the insulation required to achieve Passive House standards.
A variety of methods achieving superior insulation exist currently. I researched many on my journey to establish Historical Innovations. The largest challenge I believe that homeowners face is the high cost of specialized materials and labour to build in this manner. Most builders of tract housing have little to no incentive to build to such an extremely efficient standard. Short term construction cost savings are traded for long term operating cost increases. The average home costs more to heat, cool and maintain over a 40 span than does the cost to build it. As we see energy costs rise at an ever increasing rate, this will certainly become more of an incentive for consumers to demand higher efficiency standards to be common place.
Historical Innovations has a unique and proprietary methodology of building to the Passive House standard. We create walls that are so extremely efficient, meeting the stringent Passive House standard is easy for us.
Superior Insulation: Our wall systems incorporate an unapparelled level of thermal insulation. The thermal insulation values are scalable and can be built to accommodate any climate and any home. Additional building shape and design factors during planning are considered as we want to maximize the use of our unique wall system throughout a project. Inside and outside walls are constructed with stone.
Thermal Mass: These walls are heavy, so heavy in fact that we can't ship the stone walls, they have to be formed and made onsite and in situ. 1 ton per square meter. That is the weight of a small car in an area of wall the size of your refrigerator. This thermal mass acts as a thermal battery for holding heat energy in the winter and moderating temperatures in the summer.
No Thermal Bridging: Our walls are built without any thermal bridging. So the cold stays outside and cannot penetrate the insulation barrier separating the inner and outer wall systems.
Decremental Delay: The thermal mass embodied within the walls has the benefit of a little known thermal property called decremental delay which is thermal buffering.
The term ‘decrement delay’ refers to the time it takes for heat to pass through an element of a building (such as an external wall or roof). Typically this is taken to be the delay in hours between the peak temperature of the outer surface of the element and the resulting peak temperature of the internal surface.
This concept reflects increasing awareness that the thermal behaviour of buildings is dynamic, rather than static, and that thermal mass, as well as thermal insulation, has a significant impact on the energy efficiency of a building. For example, two buildings with identical U-values (R value of insulation) may perform very differently depending on their decrement delay, with a longer delay likely to reduce peak loads on building services systems and thereby be more efficient.
We construct the inside and outside walls separately and we fill the cavity between with highly efficient closed cell urethane foam insulation. A monolithic stone wall system is the result.
Our walls could be utilized in a fortress they are so strong. Beyond that, they require virtually zero maintenance beyond sporadic cleaning as the years pass.
Air Quality: Passive House has stringent air quality requirements. In fact it is central to comfort, occupant safety and the longevity of any structure. We incorporate both passive and active air filtration and exchange systems in our designs to ensure controlled air exchange within a building. This promotes occupants health and the health of the building itself.
Once the walls are unveiled from the modular construction forms, in that very moment, you realize that they will be standing forever. No further finishing is required and they provide a highly aesthetic appearance right out of the forms. No painting, no drywall and no plastering on the inside. No siding, no stucco, no finishing on the outside. Just beautiful monolithic stone walls to stand the test of time.
The one thing that we must ensure is a forward thinking design team; once these walls are formed, they will be very difficult to change and we need to ensure that our workmanship and design is perfect. It will stand as a testament to our dedication for generations.