The Passive House Institute (PHI) is an independent research institute based in Darmstadt, Germany that has played a pioneering role in promoting ultra-low energy construction through Passive House building standards and principles. With rising awareness of climate change and the need to dramatically reduce energy consumption from buildings, the passive house approach developed by PHI has become an influential model for sustainable building around the world.
The Passive House Institute: Pioneering Energy-Efficient Building Standards for a Sustainable Future
Origins of the Passive House Institute
The Passive House Institute was founded in 1996 by Dr. Wolfgang Feist, a German physicist and Passive House pioneer. Feist had been researching ultra-low energy buildings since the 1980s and co-designed the first Passive House in Darmstadt in 1990. This residence used 80-90% less energy for heating and cooling compared to typical buildings at the time.
Impressed by the performance of this prototype home, Feist established the Passive House Institute to further research and develop Passive House principles, as well as promote their widespread adoption. The Institute has played a crucial role in defining the Passive House Standard - a rigorous voluntary standard for maximizing building energy efficiency.
Key Activities and Services of the Passive House Institute
Over the past 25+ years, the Passive House Institute has become the leading international authority on Passive House best practices. Some of its key activities and services include:
- Research and refinement of Passive House design principles
- Scientific testing and analysis of Passive House performance
- Development and administration of the Passive House certification standard
- Design and enhancement of highly efficient Passive House Components
- Training and certification of Passive House designers and consultants
- Quality assurance through auditing and certification
- Policy advocacy and stimulating the growth of Passive House
- Extensive education, outreach, and information services
The Institute has also collaborated with over 50 organizations worldwide to promote local passive house networks and solutions adapted to different climates and contexts.
The Passive House Standard - Setting the Bar for Energy Efficiency
The Passive House Standard represents the most rigorous voluntary energy standard for buildings in the world today. To achieve certification, a Passive House must meet several strict criteria:
- Space heating demand of max. 15 kWh per sq meter of living space per year
- Total primary energy demand (for all uses including heating, cooling, lighting, hot water, appliances, etc.) of max. 120 kWh per sq meter living space per year
- Airtightness - maximum 0.6 air changes per hour at 50 Pascals pressure
To optimize performance, Passive Houses employ a combination of robust superinsulation, airtight envelopes, energy recovery ventilation, high-performance windows, and careful detailing and design. Reducing heating/cooling loads enables the use of minimal systems, often entirely met by the heat from occupants, appliances, and passive solar gains. With total energy use slashed by up to 90%, Passive Houses offers a proven path to truly sustainable buildings with minimal carbon emissions.
The Passive House Standard has been implemented in all types of buildings worldwide, from individual homes to entire communities and high rises. Over 50,000 buildings have now been certified to the Standard. Many variants have also emerged for different climates, such as the EnerPHit Standard for retrofits and the PHI Low Energy Building Standard for warmer regions.
Key Milestones for the Passive House Institute
Some notable milestones and achievements for the Passive House Institute include:
1996 - Passive House Institute founded in Darmstadt by Dr. Wolfgang Feist
2000 - First Passive House high rise built in Hanover
2002 - The First Passive House Standard introduced
2007 - First Passive House school built in Frankfurt
2011 - 20,000th Passive House certified
2015 - The International Passive House Association formed
2018 - One-millionth square meter of Passive House construction certified
2020 - Passive House popularity growing exponentially worldwide
The Institute's research and advocacy have been crucial in moving Passive House from a niche concept to mainstream adoption globally. Today, the Passive House Standard is widely recognized as one of the most effective solutions for achieving the dramatic cuts in emissions from buildings needed to address climate change.
Key Components of Passive House Design
Passive House buildings achieve remarkable energy efficiency through careful attention to a few key elements in their design and construction:
Superinsulation: Passive House envelopes are extremely well-insulated, with wall insulation up to 14 inches thick. This dramatically reduces heat loss through building shells.
Airtightness: Air barrier systems are used to minimize leakage through cracks, seams, and penetrations. Passive House standards call for leakage rates below 0.6 ACH. This prevents energy loss while ensuring good indoor air quality.
High-Performance Windows: Triple-paned windows with insulated frames minimize thermal bridging. Overall window U-values are 0.14 or less in colder climates.
Ventilation System: Continuous mechanical ventilation provides fresh air, while highly efficient heat recovery systems recover 80-90% of heat before exhausting stale air.
Solar Passive Design: Passive solar gains are utilized through orientation, sizing of glazing, shading, and other strategies.
Thermal Bridge Free Construction: Careful detailing and insulation installation minimizes thermal bridging through wall-to-floor joints, balcony attachments, etc.
Renewables: Solar PV, solar thermal, and other onsite renewables can help achieve Net Zero Energy and offset remaining loads.
By bringing together these elements in an integrated fashion, Passive House buildings achieve remarkable reductions in energy use with minimal technology. The Passive House approach exemplifies how effective bioclimatic building design can be.
Passive House versus Other Efficiency Standards
The Passive House Standard stands apart from other building energy standards in its rigor and performance outcomes:
LEED and EnergyStar: These rating systems have helped improve mainstream building practices but do not have defined energy targets. Buildings only need incremental improvements over minimum code.
Net Zero Energy: Focuses on net annual energy use but does not address peak winter loads. Does not necessarily require well-insulated envelopes.
EnerPHit Standard: A variant of the Passive House Standard for retrofits of existing buildings, with slightly relaxed criteria.
PHI Low Energy Building Standard: A Passive House variant for hot and tropical climates focused on reducing cooling loads through shading, ventilation etc. but allows higher heating demand.
The original Passive House Standard remains the most comprehensive approach to optimizing building energy performance through passive principles and robust envelopes.
Global Growth of Passive House
Over the past two decades, Passive House has gone from a niche concept in Germany to a global movement with buildings on six continents. By 2018, the total global floor area certified to the Passive House Standard surpassed 10 million square meters.
Austria, Germany, and Switzerland continue to lead in Passive House construction, but dramatic growth has occurred more recently in Belgium, the Nordics, North America, and China. Many cities and regions have adopted Passive House policies or incentives. The Standard has also spread far beyond Europe to places like Singapore, Malaysia, Brazil, and Canada.
Passive housing is now entering the mainstream in some countries. In Brussels for example, Passive House certification is effectively mandatory for all new construction. The movement toward Passive Houses accelerates as global warming concerns grow and its cost-effectiveness improves with scale.
Costs and Cost Effectiveness
A key question often raised about Passive House construction is whether the higher upfront costs are justified by energy savings over time. Numerous studies have confirmed the cost-effectiveness of Passive House.
While costs can vary significantly by building type and location, Passive House does generally incur 5-10% higher upfront costs compared to conventional buildings. However, total lifetime costs are lower. One key study by the Passive House Institute found the following*
- Investment costs: 7% higher
- Life cycle costs over 30 years: 7% lower
- Simple payback period: 11 years
With increasing scale and competition, these costs continue to fall, particularly as Passive House becomes mainstream in some regions. For instance, single-family Passive Houses in Belgium average just 2-3% higher costs today.
(*2007 study of residential buildings by Passive House Institute)
Studies have also highlighted the positive economic impacts of Passive House beyond the building sector. Widespread adoption stimulates innovation, creates green jobs, improves resilience, and reduces healthcare costs through occupant health benefits. In short, the evidence clearly shows Passive House offers one of the most cost-effective routes to building decarbonization.
Passive House Certification Process
To have a building certified as a Passive House, a certification process administered by the Passive House Institute must be completed. The key steps include:
- Early Stage PHPP Feasibility Study: Energy modeling is done using the Passive House Planning Package software to prove compliance is feasible. Design tweaks can be made to aim for certification criteria.
- Engage Certified Passive House Designer: While not mandatory, it is highly recommended to work with a designer/consultant specially trained in Passive House.
- Detailed PHPP Verification: The PHPP model is refined with detailed construction data to verify criteria will be met.
- Quality Assurance: On-site audits and testing are conducted during and after construction by a Passive House certifier. Air tightness testing and commissioning of systems are mandatory. Thermal imaging can also be used to detect any flaws.
- Final Certification: If verification and quality assurance steps check out, the Passive House Institute will issue a final Passive House certificate.
Certification ensures Passive House criteria have truly been met. The PHI also provides optional project validation and builder licensing programs. Many clients will specifically demand official Passive House certification.
Benefits and Impacts of Passive House Buildings
Moving from conventional to Passive House construction provides a wide range of benefits and positive impacts:
Energy Savings: Heating energy is reduced by up to 90% and total building energy by 60-70%. Average Passive House uses 1/10th the energy for heating of typical new buildings.
Operating Costs: Dramatically lower heating, cooling, and power bills. Lower maintenance costs.
Occupant Health and Comfort: Continuous ventilation improves air quality. Elimination of drafts and improvement of surface temperatures provide superior comfort. Studies show significantly higher occupant satisfaction.
Asset Value: Higher valuation and faster sales or leases of Passive House buildings documented in several studies.
Mitigating Global Warming: Passive House is a crucial tool for achieving carbon neutrality in the nearly 40% of global emissions from buildings.
Resilience: Improved ability to maintain habitable conditions during blackouts or fuel shortages.
Air Quality: Improved indoor air quality and less likelihood of mold growth.
Construction Quality: Certification requirements often lead to higher build quality and durability.
The holistic benefits of Passive House make it a highly compelling real estate investment and a vital climate change solution.
Key Trends in Passive House Construction
Passive House as a building approach continues to evolve in new directions:
- Toward Net Zero Energy: Many Passive Houses now add renewables like PV to achieve net zero annual energy use.
- Use of Natural Materials: Increased focus on avoiding foam insulation and using sustainable solutions like cellulose, wood fiber,r and straw bales.
- Cost Reductions: Wider availability of affordable Passive House solutions to drive down costs further.
- Focus on Embodied Carbon: Growing attention to reducing carbon emissions from material production and construction in addition to building operations.
- Scaled Implementation: Construction of larger Passive House districts as opposed to just individual buildings. Also, Passive House retrofit of entire public housing estates.
- Mainstreaming: Voluntary and regulatory measures to make Passive House a baseline standard for new construction, as seen in Brussels.
- Climate Specific Standards: Continued adaptation of Passive House for different climates, especially warmer regions.
- Innovation in Components: Highly insulating vacuum insulated panels and aerogel insulation steadily improving. Development of cheaper triple-pane windows.
Passive House continues to evolve as the most effective standard for achieving building energy efficiency, occupant health, and climate change mitigation.
The Passive House Institute US Component Database
An invaluable resource provided by the Passive House Institute US is its Component Database of approved passive house products. The database allows easy searching of thousands of Passive House suitable components needed for PH construction.
These include windows, doors, insulation, HVAC systems, heat recovery ventilators, air sealing products, and shading solutions. Only products that meet strict Passive House criteria are listed. The database is searchable by component type, manufacturer, and specific properties.
For each product, detailed technical specs are provided on:
- U-values, R-values, and solar heat gain coefficients
- Air tightness ratings
- Noise levels
- Pressure testing and quality ratings
- Sizes and dimensions available
- Product photos and diagrams
- Pubic availability and links to manufacturers
Builders can easily access information to identify approved components for their specific needs. The database accelerates and simplifies the design process. It also provides transparency on product performance. Manufacturers benefit by having their products recognized.
The database covers products available in the United States. Similar databases are maintained by Passive House chapters in other countries. As a repository of proven solutions, the Component Database has become an invaluable asset for driving Passive House mainstream.
Passive House Training and Certification Programs
To build competence in properly designing and constructing Passive House buildings, PHI offers several key education programs globally:
Certified Passive House Designer/Consultant Course: This is PHI's core training for passive house designers and consultants. Different versions are offered for architects, engineers, and construction professionals. The multi-day courses teach the fundamentals of passive building physics, energy modeling using the PHPP software, and Passive House certification.
Passive House Tradesperson Course: Shorter course for building trades like carpenters, insulating contractors, and HVAC technicians to learn proper techniques for Passive House construction and retrofits.
Passive House Building Certifier Training: Intensive program to train professionals in proper quality assurance procedures using blower door testing, thermography, on-site audits, and commissioning.
Online Passive House Courses: More accessible online versions of PHI's core courses for self-learning by individuals.
The Institute has certified over 35,000 architects, consultants, and construction professionals globally, building an army of qualified passive house experts. PHI also partners with universities to offer graduate-level passive house education. Proper training is key to ensure buildings achieve certification and perform as designed.
The International Passive House Association (iPHA)
The International Passive House Association is the worldwide network for promoting the Passive House Standard and connecting the global community of Passive House builders and experts. The PHA was founded in 2015 through the initiative of several leading international Passive House organizations.
The iPHA aims to accelerate the adoption of Passive House globally through advocacy, information sharing, new research, training, and bringing together the world's Passive House experts. It represents the interests of Passive House at the global level including at international organizations and events like the UN and COP meetings.
The iPad's core members are leading regional Passive House associations from around the world, currently including:
- Passive House Institute (Germany)
- Passive House Canada
- Passive House Institute US
- Passive House Institute China
- Passive House New Zealand
- Passive House Alliance (Australia)
- Passive House Platform (Belgium)
- Passivhus Norden (Nordic)
- Plateforme Maison Passive (France)
- Passiefhuis Platform (Flanders)
Together these organizations represent over 50,000 building experts committed to Passive House. The iPHA brings them together into one global movement while allowing regional flexibility.
The iPHA organizes an annual International Passive House Conference to connect members and share knowledge. It also publishes the Passive House International journal and Passipedia website - an online Passive House resource. Through its global network and activities, the iPHA strives to make the Passive House Standard a worldwide solution for sustainable buildings.
The Future of Passive House
With climate emergency demanding immediate action, Passive House represents one of our most effective tools to achieve rapid reductions in building energy use and carbon emissions. The Passive House Institute pioneered this ultra-low energy approach and has provided the worldwide standard, scientific research, and training programs that have made Passive House a proven reality today.
Key trends like policy adoption, cost reductions, climate-specific standards, and innovative components will continue to drive Passive House into the mainstream globally. As the urgency of addressing global warming grows, Passive House will offer a critical path for the building sector to achieve carbon neutrality through good building physics and design. The Passive House Institute will continue providing the scientific foundation, technical resources, and high standards needed to realize passive buildings on a massive scale worldwide.
The Passive House Institute has demonstrated an invaluable commitment to researching, codifying, and propagating ultra-low energy building principles over the past 25+ years. Its rigorous Passive House Standard and the global community of expertise built around it provide a proven model for achieving the deep cuts in emissions from buildings urgently needed. With climate change accelerating, Passive House represents one of our most effective tools for building sector decarbonization through good physics and design. The Passive House Institute will continue providing critical thought leadership and high-quality training to drive Passive House into the mainstream globally. If embraced fully by governments, architects, builders, and the real estate industry, Passive House can become the new normal in building energy efficiency, improving affordability, comfort, and resilience while making an enormous contribution to protecting our living planet.
