Decarbonization and Resilience: New Phius Retrofit Standard Open for Public Comment

This guest blog post was written by Graham S. Wright and originally published on on February 02, 2024.  

Phius is seeking public comments on the new health and resilience-based, carbon-focused Phius REVIVE 2024 passive retrofit standard.

To make wide-scale retrofitting of the existing building stock possible, we’ve spent the last several years formulating an innovative and adaptable passive retrofit standard. We’re happy to report that it is now ready for public review, and we invite your input 

There are a variety of challenges associated with energy and decarbonization retrofits. There is the question of how deep to go with building-level upgrades versus cleaning up the energy supply to the building. There are many kinds of buildings in various states of repair. Developers and project teams need to know what value the investment will produce. 

We have reconsidered the retrofit question from the ground up, and the result is a trailblazing new standard that puts mass-scale passive retrofitting of the existing building stock within reach: 

Phius REVIVE 2024 

The revolutionary Phius REVIVE 2024 framework is differentiated from other retrofit standards in the following ways:

  • The planning process is guided by resilience (which we deem a must-have safety feature in a world adapting to more extreme weather events).
  • It goes for zero operational carbon emissions and is sensitive to embodied carbon.
  • It features a software tool that can run parametric studies to identify a range of specific solution packages that all have the required resilience and with the lowest life cycle costs.
  • A quality process ensures results.

Please review and comment on Phius REVIVE 2024 by March 15, so we can ensure its success! 

The scope of Phius REVIVE 2024 includes a wide variety of buildings in all climates. But no matter the building type, the standard assures a safe and healthy living environment for inhabitants. This includes: 

  • Resilience to grid outages, meaning the interior temperature remains livable for at least a week in the event of an extreme heat or cold event 
  • Resolving existing indoor air quality issues such as mold, radon, lead or poor ventilation 
  • Fortification against site hazards such as hail, wildfire and high winds where appropriate 

Deep energy retrofits can be a challenge, especially when considering the environmental carbon impact of the work and new materials. Phius REVIVE 2024 addresses this concern in several ways: 

  • It helps project teams make decisions about whether and how far to go for a specific project. For example, it asks, “what are the remaining life spans of the existing building components?”  
  • It prioritizes decarbonization: 
    • Operationally, direct emissions cease shortly after construction because electrification is phased in early. 
    • For embodied carbon, a new life-cycle cost metric weighs the carbon cost of high embodied carbon measures and high electric grid peak loads when recommending the scope of work and how extensive the conservation measures should be. 

As is the case with all other Phius Standards, Phius REVIVE 2024 includes third-party quality assurance—here the process is based on ASHRAE Commissioning guidelines. This guarantees performance as designed while also providing the following benefits: 

  • It allows phased retrofits. 
  • It suggests elective requirements that provide additional benefit to the owner. 
  • It includes post-construction monitoring and commissioning to assure continued performance. 

In an effort to create a retrofit standard that can be applied as widely as possible, Phius REVIVE 2024 was designed to facilitate widespread adoption. This includes: 

  • Providing an open-source software engine for calculating the resilience and cost performance metrics. 
  • The standard is written in a way that makes it easily adoptable for other organizations and municipalities. 

Phius REVIVE 2024 was designed and written with the intention of it becoming the mainstream solution for mass-scale retrofits across the globe. For it to make it there, we need your help to test and hone the standard to ensure it is clear, digestible, and appealing to homeowners and developers alike. Please review the standard and submit your comments by March 15.  The buildings of today are our greatest asset – help us REVIVE them! 

Find resources related to Phius REVIVE 2024 and the accompanying software here. 

Members of the Phius technical staff contributed to this post. 

By Graham S. Wright, PhD, Senior Scientist & Chair of the Phius Technical Committee