Buildings use 40% of all energy in the United State, but surprisingly consume 70% of the electricity produced and are the largest producers of CO2 emissions. Scientists predict that CO2 and other greenhouse gases will cause profound environmental damage, including rising sea levels, flooding, drought and the spread of diseases.
Energy Assurance can help change this.
Because buildings have an average 50 year life span, it is possible to impact future CO2 emissions in a big way. By employing passive building strategies in new buildings we can reduce building energy demand by 75% for their lifetime. Luckily we can do this today.
Should a building owner pursue passive building strategies, buildings will operate at 14.0 kBTU/sf/year by conserving energy first, before adding renewable energy sources. Meeting this performance target enables the project to lead the way to Zero Energy with the addition of renewables, serving as a beacon for where innovation and popularity intersect.
Creating places and spaces to attract world leading companies and world leading staff requires the employment of forward-thinking strategies that demonstrate vision and address real problems.
In Silicon Valley, one high performance building, 435 Indio Way, reduced its energy consumption to zero with the addition of natural daylighting strategies and solar PV. The developer took these steps to save money, however it enabled the tenant to attract top talent from the new generation of workers whose social conscientiousness requires awareness of global issues and more simply, requires a comfortable place to work.
The PassivHaus design movement has been the most effective design approach to reducing building energy use for over 25 years around the globe. Although PassivHaus design began in residential buildings, it is now widely used in many other building types including offices, hotels, libraries, museums, and schools. The passive building strategies developed by the PassivHaus Institute include a quantifiable performance standard that can be implemented in most building types. Buildings that meet this high performance building standard use dramatically (up to 80%) less energy and provide better indoor air quality and thermal comfort than those designed to conventional codes. This design approach also provides greater resiliency and survivability during extreme weather events.
Passive building strategies lower the amount of operating energy in a cost effective manner by applying conservation measures first. In this way it is practical to supply all of a building’s energy needs with relatively low levels of renewable sources. As a result, passive building strategies are the ideal foundation for net zero energy buildings.
A Passive House design relies on a few foundational principles to achieve extreme energy efficiency, comfort, and resiliency:
- Airtightness: the building envelope is extremely airtight, preventing infiltration of outside air and loss of conditioned air as well as ensuring moisture free assemblies.
- Balanced ventilation with Energy Recovery Ventilation: some form of balanced heat and moisture recovery is required in most climates.
- Thermal Bridge-Free construction: the building envelope is designed to eliminate thermal bridges. (A thermal bridge is a highly conductive material that extends from within a building’s envelope to the outside air.)
- Continuous insulation: higher than typical levels of continuous insulation are included through the entire envelope.
- High-Performance Components: high- performance windows (typically triple-paned for cold climates) and doors provide thermal comfort and building durability.
- Shading and Solar Design: solar gain is managed to exploit the sun’s energy for heating while shading elements work to minimize overeating in cooling seasons.
Passive building strategies are low-tech, with few moving parts, so buildings are durable and have minimal maintenance needs. Passive House design carefully models and balances a comprehensive set of factors—including heat emissions from appliances and occupants—to keep the building at comfortable and consistent indoor temperatures throughout the heating and cooling seasons, using as little active energy input as possible.
Passive building strategies do not radically differ from conventional building, but require special balancing and care through both the design and construction stages. The passive building designer uses software to adjust multiple variables—insulation R-values, wall construction parameters, etc.—until the design model meets the energy performance targets. Construction crews must learn and apply approaches to air sealing and thermal bridges. As a result, to assure performance, a project will undergo stringent third-party quality assurance and quality control inspections, including final testing and commissioning of the mechanical systems.
Passive building strategies do not dictate an aesthetic—they have been successfully applied in traditional as well as contemporary and minimalist designs.
Larger buildings are economical candidates for passive building for a variety of technical reasons, including economy of scale and a more favorable volume-to-surface-area ratio. Passive House multifamily projects have cost approximately 0% – 4% more than conventional multifamily buildings. A recently completed passive apartment building in Brooklyn, referred to in the One City, Built to Last report that the New York City Mayor’s Office published in 2014, did not have a cost premium compared to a conventional building.