Old Alt New is committed to Passive House, not the status quo.
You are not required to achieve Passive House standards, but we are.
Every Old Alt New project pursues Phius Passive House standards. Passive House project registration and certification are not required, but passive house benchmarks are the target.
What is Passive House and passive design?
Passive House is an approach to design, build, and opperate high-performance buildings.
Passive House buildings require dramatically less energy - up to 90% less energy - to heat and cool than conventional buildings. Using less energy reduces the building’s operational carbon emissions and the global warming contributions that come from the production of energy.
To achieve such high levels of energy performance, Passive House buildings focus on three main stategies:
a super-insulated exterior envelope that helps maintain a very steady and comfrotable temperature with minimal heating and cooling
an air-tight exterior envelope that eliminates unwanted drafts and moisture from entering the building’s materials and interior environment
an all-electric heating, cooling, and ventilation strategy that maintains target temperature levels, fresh air and oxygen levels, and even humidity levels all year long
Passive House 101
Take a look at this breif explainer video from the folks at Passive House Accelerator, one of the best sources and a leading proponent of high performance design and construction.
Wikipedia’s ‘Passive House’ Definition:
Passive house [derived from the German term ‘Passivhaus’] is a voluntary standard for energy efficiency in a building, which reduces the building's ecological footprint. It results in ultra-low energy buildings that require little energy for space heating or cooling.
The standard is not confined to residential properties; office buildings, schools, kindergartens and a supermarket have also been constructed to the standard. The design is not an attachment or supplement to architectural design, but a design process that integrates with architectural design. Although it is generally applied to new buildings, it has also been used for refurbishments.
What are the bennefits of a Passive House?
The Passive House building standard is recognized as the global ‘gold standard’ in high-performance design and construction.
What does high-performance really mean?
Health - Mechanical ventilation provides filtered oxygen-rich fresh air and remove stale CO2 across the entire building.
Comfort - When propoerly designed, every corner of a Passive House building remains within a specified temperature and humidity range every day, all day, every season, all year.
Quiet - Tripple glazed windows, leak-proof doors, and super-insulated walls make Passive House buildings one of the best ways to combat urban nusance noises.
No Dust - With an airtight envelope and filtered mechanical ventilation, outdoor dust is stopped from entering and indoor dust is pulled out of the air throughout the day.
No Bugs - An airtight envelop, windows, and doors eliminates the most common entry points for bugs and critters to enter a building.
No Unwanted Moisture or Odors - Part of a balanced ventilation strategy, cooking odors and kitchen and bath humidity are exhausted at their source, stopping their spread and removing them from the building interior.
Durable Construction - One of the “side-effects” of airtight construction is improved building quality. Water, moisture, and condensation lead to failures. Passive House buildings are substantially more durable to these common points of failure.
Predictable Performance - Every Passive House design is informed by building physics and energy modeling. The predicted energy use of a Passive House building is something that designers, engineers, and homeowners can count on to right-size equipment and down-size energy intensive equipment.
Affordable Utility Bills - Passive House strategies lead to lower monthly energy bills and reduced building maintenance costs.
Energy Efficiency - There is no better way to conserve energy than to implement Passive House strategies. Reducing peak energy demands are good for your budget and good for the energy grid.
Complementary Solutions - An ultra-efficient Passive House combines well with solar panels. The reduced energy demand of a Passive House can easilty be served with a modest solar panel aray on the roof.
Resilient to Climate Change - Across the globe, climate change is leading to more extreme weather events, more wild fire smoke events, and less predictable high and low temperatures. Passive House buildings do their part to minimize these changes, but they are also the buildings best equiped to deal with these changes safely and comfortably.
How does a building achieve Passive House standards?
Passive House Design Principles:
Continuous Insulation - A consistent and un-broken layer of insulation across all exterior surfaces of a building maintains indoor temperatures and helps reduce condensation from developing.
No Thermal Bridges - Thermal bridges are like ‘short cuts’ that undermine the effectiveness of a building’s insulation. Eliminating thermal bridges saves energy, improves comfort, and reduces any chance of condensation and mold from developing.
Airtight Envelope - Like a high-tech windbreaker, proper air-sealing and detailing is key to allowing insulation to work to its full potential - and just as important - letting unwanted water vapor exit a building’s layers to let them stay dry.
Exceptional Windows & Doors - Windows and doors represent the biggest ‘holes’ in a building’s thermal envelope. That’s why well-insulated, properly detailed, and tightly sealing windows and doors are so important to minimizing thermal losses (and delivering daylight, sunshine, and views to the outdoors).
Fresh Air Ventilation with Heat Recovery - “Balancing” fresh supply air and stale exhaust air keeps the interior air clean and full of oxygen. Meanwhile, heat and energy recovery ventilators (HRVs and ERVs) extract heat between incoming and outgoing air to pre-condition outdoor air before it enters the interior, which saves energy on heating and cooling.
Solar Shading - In the summer, solar heat gain (heat from the sun which enters through glass windows) is one of the biggest reasons why buildings need air conditioning. Shading the summer sun, while preserving views to the outside, reduces glare and the amount of cooling needed.
Building Orientation & Form - When possible, adjusting a building’s shape, envelope-to-interior ratio, and window positions relative to the sun’s path through the sky can help designers better control both the possitives and negatives that the sun’s heat can offer.
Solar Daylight & Solar Heat Gain - Free natural light and free solar heat are welcome contributions to a building - so long as they are planned for in advance. Balancing wanted solar heat in the winter with unwanted solar heat in the summer is where careful modeling comes into the design process.
Moisture Management - Protection from ‘bulk’ water (rain, snow, ground water), letting materials dry after they’ve become wet, and balancing membrane and material vapor profiles to let airborn water vapor pass-through assemblies (or not) is where building physics and architectural detailing come together. Discussing moisture management what seperates Passive House nerds professionals from their peers. (We love nerds!)
Efficient Water Heating & Distribution - In efficient buildings, the domestic hot water heating system is one of the biggest consumers of energy. Effient equipment and a compact distribution system save on first costs and operational costs.
All icon graphics courtesy of Passive House Accelerator: https://passivehouseaccelerator.com/passive-house
Does a passive houses cost more than a ‘status quo’ or ‘code minimum’ house?
This is a tricky question to answer, but it’s important to be as straight-forward as possible. Passive House projects are based on building science - performance numbers speak for themselves - and so should the dollars and cents. It’s up to you to decide what’s most important for your project.
Yes.
Energy Performance Modeling: During the design phase, energy performance modeling is an important part of fine-tuning the solar exposures, exterior assemblies, window performance characteristics, and equipment sizing. It is also necessary for passive house certification. Iterative modeling adds time to the design process, but is esential to a high-performance building. Modeling can even help save money by directing the project budget to the areas that make the most impact.
Inexperienced Builders: Meeting code minimum is still the norm today. Without prior experience or training, building to passive house standards still seem intimidating to many builders and sub-contractors - some may pad their fee to cover the learning curve of building up to a higher standard.
Skilled Builders: Those who are capable of delivering passive house levels of construction know that they are some of the best builders and sub-contractors out there. In a competitive market, these skilled builders know that they offer something special, and may charge for it accordingly.
Windows & Doors: Most certainly, the added quality and characteristics of passive house quality windows and doors will cost more than that of a status quo building. (And that extra performance and quality is worth the added cost!)
Insulation & Air Sealing: Every building today needs insulation and at least some attension to gap and hole sealing, but building a passive house project will require about double the insulation material cost (but not double the labor cost) and a bit more time and care from all trades that come in contact with the airtight layer (a marginal increase in material costs, but a bit more in added time and labor).
Certification: Having your project certified and fully-recognized as a Passive House project will involve a good deal of paperwork, scheduling, and testing by your design and construction team - and the involvement of one of the two qualifying Passive House programs (PHI or Phius). Certification is not necessary to achieve an incredibly high-performing project, but there is no better way to keep the entire project team on point from start to finish than persuing certification.
In short, a project’s 'first costs’ - or the the money it takes to get from the start of design to the end of construction - tends to be 3-8% higher for a passive house project than a status quo building. It doesn’t have to be that way and this isn’t an absolute fact, but this is common for most projects.
No.
Passive House projects save money every month they operate. Utility bills are lower (or even non-existent) and annual maintenance costs are reduced versus a status quo project. These monthly savings can “payback,” or make up for the added first costs, in 5-20 years.
What also needs to be considered is added value. One can certainly design and build a cheaper building, but that building will not have the same value as a passive house project. Durability, comfort, climate resilience, and occupant health each hold value, but it’s up to you to decide if that added value is worth the money necessary to include it in your project.
HVAC Equipment: The heating, ventilation, and air conditioning equipment in a status quo building and a passive house project are very different - but HVAC equipment and distribution systems are needed in all projects. Status quo buidings with inacurate energy estimates need larger, louder, and more energy-intensive equipment to heat and cool a leaky code-minimum-insulated project. Instead of oversized equipment, passive house projects use smaller and more efficient equipment. The cost differences between these two different aproaches is often neglegable.
Designing a Passive House from the Start: It is more expensive to ‘upgrade’ a fully-designed status quo house to passive house standards than it is to design a passive house from the start. Passive design strategies are much more holistic than simply adding extra insulation and swapping out one window type for another. Using passive design strategies from the begining (building orientation, interior layout, biulding form) only makes it easier and less expensive to achive Passive House performance standards.
Rebates and Incentives: Many states, local municipalities, and energy providers are offering rebates and incentives to include all-electric utilities, adding solar panels, or achieving high performance standards such as Passive House. It’s worth some research to see what incentives might be available in your area.
Useful Cost-Related Articles:
Office of Energy Efficiency & Renewable Energy: Why Energy Efficiency Upgrades
NerdWallet: How Energy-Efficient Upgrades Can Increase Your Home’s Value
USA Today: Buying an Energy-Efficient Home is a Financially Bright Idea
Financial Wellness Center: Energy Efficiency: Is it Worth it?
PROBuilder: Can Building a Passive House Cost the Same as a Code-Built Home?
Green Building Advisor: Building a Passive House for $163 per Square Foot
Phius: Passive House FAQs
Green Building Advisor: Payback Calculations for Energy-Efficiency Improvements
Passive House standards come in two great flavors - original German and new American. Each standards handels allowable energy calculations and climate-specific considerations differently. Both are based on decades of scientific research and both are committed to improving the performance of buildings.
Passive House standards and certifiers.
(PHI)
The PHI is a research institute based in Darmstadt, Germany. Founded in 1996, the PHI was responsible for creating the first widely-recognized passive house certification standards.
PHI set passive house standards for energy use, airtightness, and thermal bridging limitations. Although the standards were developed for projects in Central Europe’s moderate climate, PHI’s standards are universal and create a set limit for projects in any climate region across the globe.
Passive House Institute US
Phius is built off the research of the Passive House Institure, but broke away in 2011 and developed its own standard in 2015.
Phius has climate-zone-specific energy targets, which create more atainable certification targets for very hot, very cold, and very humid climate zones.
Phius has also adjusted its targest to consider and favor atainable and cost-effective approaches to passive house design.
Stewart Gohringer, Old Alt New owner and architect, has been a Phius Certified Passive House Consultant (CPHC) since 2023.
Old Alt New projects pursue the Phius standard, but we are cheering for Passive House projects that follow either standard.
