Guidance on Retrofits and Decarbonization for All Buildings

32tev__gEmbodied carbon is an important and complicated subject. Phius Senior Scientist Graham Wright helps sort it out and discusses Phius’ new REVIVE program in this post.

Let’s talk about retrofit, starting with the proposition that we need to decarbonize all buildings by 2050.

Stopping direct emissions is a good start; the electrification crowd is right about that. But only stopping direct emissions just moves the burden onto the utility/energy supplier, and they have to contend with transportation electrification as well.

The key question for the building sector, and for society at large, is how much effort/investment to put into increasing the clean energy supply, versus reducing the demand by such measures as passive building and heat pumps.  

The scale of the required transition is daunting no matter which way we approach it, especially considering that we have to do all of this utility infrastructure and building retrofit work without throwing off a lot of emissions in the process. The embodied carbon crowd is right about that, though I think a materials focus doesn’t go far enough.  

One way to get at the balance-of-investment question is with the idea of life-cycle cost. What mix of grid upgrades and building upgrades minimizes the total cost of getting the job done, on an annualized/life-cycle basis? I brightened up to this when it occurred to me that carbon could be included in that calculation by including a cost of carbon. Let’s use full-cost accounting!  

That price might be set based on the cost of, say, direct air capture of CO2, that is, at some point it becomes cheaper to actually pull the carbon back out of the air. The full-cost metric I am thinking of would include all of the following:

Tentative name: Annualized Decarbonization of Retrofitted Building Cost (ADORB Cost)

ADORB Cost = sum of the following components, each an annual/annualized cost:

  • Direct energy cost. E.g. site kWh * $/kWh = $
  • Direct building retrofit measures cost (material & labor) including building-level electrification cost. E.g. ft3 of stuff * $/ft3 = $
  • Social cost of carbon, upfront/embodied. CO2e kg * $/kg = $
  • Social cost of carbon, operating. CO2e kg * $/kg = $
  • Energy system transition cost (e.g. new utility solar + storage). $/MWh * MWh = $

The idea would be that a baseline cost in this sense is calculated for the scenario of continuing to operate and maintain the building as is for some decades. Any proposed retrofit should at least have a lower cost than that, hopefully much lower. Basically one designs as if there’s a carbon price. (In a baseline case I calculated for my apartment, 70 percent of it was the carbon cost of continuing to operate the gas furnace and water heater, even after the grid electricity was completely decarbonized).

This seems useful, but there are a few issues with it, therefore it can’t be our only lens. 

Issue 1 

It would not prohibit supply chain emissions from the retrofit work. Arguably the ideal is, call it Absolute Zero: No CO2 emissions occur anywhere in the building delivery/retrofit process, supply chain, or the building operating life, at any time. We need to decarbonize everything — the whole economy. In this view, the policy stance is that any carbon capture tech is devoted to removing carbon previously emitted, not keeping up with new work.  

All the current net-zero and carbon-neutral programs have this limitation. We can’t really do everything without emissions yet, so in order to convince ourselves we are zero there all these offsets and avoided-carbon credit schemes. I’m starting to agree with the youth climate activists that this is weaselly.  

Issue 2

At the system level, it’s tricky to use cost to decide grid-versus-building investment, because those costs in turn depend on which approach we decide to scale up in the first place. Commit to industrialized retrofit construction and those costs can come down. Commit to scaling renewable generation and transmission and those costs can come down.  

Issue 3

It’s not clear how to make this full-cost metric take into account that some things just can’t happen fast enough. For example, renewable generation and even transmission may not cost that much, but siting the required high-power transmission lines from remote western wind and solar farms to eastern cities might take too long.  

Issue 4

We’ve gotten into trouble across the board lately with our global economy by trying to minimize cost without regard to resilience. It’s more resilient to do extra things to reduce building loads rather than putting the ball in the grid’s court to both decarbonize AND stay up.  

McKeesport RetrofitTherefore, I am thinking that our new REVIVE Pilot program for building retrofit needs a number of different frameworks. I have listed them below along with a few possible elements of each:

Land use

  • Retrofit, replace/redevelop, or raze/rewild?
  • FEMA hazard assessment
  • Emerging climate hazard assessment (e.g. derecho, wildfire smoke)

Decarbonization

  • Cease direct emissions.
  • Use and generate renewable energy (reconsider off-site renewables framework).
  • Re-use high-embodied carbon structure.
  • Calculate a carbon score (no criterion, just how low can you get, i.e. without offsets).

Cost/Financial/Equity

  • Calculate ADORB cost, goal to at least beat the existing condition.
  • Use load reduction, grid interactivity and storage to financial advantage.
  • Limit the cost burden on low-income people.
  • Look to make policy cases for feebates, incentives.

Resilience 

  • Design for outages and known/emerging hazards.
  • On-site/local power, microgrids, on-site/local repair parts
  • Design for low loads.

Quality and Health

  • Assess existing deficiencies (EPA indoor air quality risk list).
  • Audits: tests, energy models?
  • Commissioning & documenting that goals are met (e.g. ASHRAE 202)

Phase planning

  • Scope includes operations, not just design.
  • Plan covers both an end state and interim retrofit phases.
  • Try to cover critical loads in the first phase.

I will have a bit more to say about this at PhiusCon 2021 this October 12-15 in Tarrytown, New York. The REVIVE Pilot program is in pilot phase, looking for sample projects, and the goal is to have an on-ramp in place. The general development strategy is to evolve from informational guidance to hard requirements in an orderly way, preferably without much backtracking.  

Our existing Phius Certification program for retrofit projects remains available through the Phius CORE REVIVE 2021 and Phius ZERO REVIVE 2021 programs, outlined in Section 3 of the Phius Certification Guidebook.

Regards,

Graham

Building a ZERO Carbon Future, Together!

Katrin HeadshotPhius Co-Founder and Executive Director Katrin Klingenberg wrote this week’s blog post in advance of her “Zero Energy and the Future of Phius” webinar on Sept. 14. It covers a variety of topics related to Phius’ work and the expanded vision of the organization.

“The west is on fire, and the east is drowning.”

Those attention-grabbing words were the first thing I heard when I turned on my TV the other day.

“The levees held, but the power grid folded”

That was a headline from the day after hurricane Ida swept across Louisiana. Most of the state was left without power; temperatures in the aftermath were predicted to rise into the 100s, all after a ton of rain and flooding. The combination of high temperatures and humidity is life-threatening — on top of all the other hardships brought on by the storm.

And then there was the Texas winter with the grid folding and people and pipes freezing in homes…

The urgency is clear. At our most recent Phius board retreat there was consensus: we are in dire straits climate-wise — it is now or never.

Since its inception, Phius’ vision has had a North Star: to create a carbon-neutral, healthy, safe, and just future for everyone by mitigating the climate crisis. And our mission is to do just that by making passive house and building standards mainstream.

The vision was extended to using passive house and building principles as the basis for all zero-energy and carbon designs. We added the Phius Source Zero certification program in 2012. Net zero is a good first step, but we need to revise the framework. In practice, net zero isn’t enough. 

The conclusion we at Phius have reached — following the thought leadership of our Senior Scientist Graham Wright — is that we need to aim to reach absolute zero in short order to avert the ultimate climate crisis. And that is absolute zero as per the original definition of zero – the absence of a measurable quantity.

A New Brand

We are upping our game on multiple levels in order to emphasize our renewed commitment to solving the ZERO-carbon puzzle for buildings. 

New Brand Same Phius GraphicWe started by reimagining the Phius brand. We are updating its look and making products and messages more relatable without sacrificing what we are known for: scientific rigor, precision, quality assurance, proven guidance, and performance. We are also unifying and expanding our suite of certifications for buildings, products and professionals. We are upping the ante on benefits to our professional members under the Phius Alliance leadership and yes, we are creating exceptionally cool swag to encourage everyone to join our tribe and make it our lifestyle together! Together, our community is creating momentum in the market — and having fun with it!

We also re-organized ourselves internally in more efficient ways over the last year, invested in a new website and a CRM, architecture. And we doubled our staff — to aim for greater, faster and increasingly exponential impact and service for our stakeholders. 

In addition, we are making dedicated efforts to reach out to communities beyond the building industry, to explain why what we do matters to everyone. Renters and owners all have a stake in what we do, and we are all one or the other. We want to give everyone an opportunity to get involved. It is up to all of us now! Join us!

Expanded Vision

Over the last decade, Phius has become the global leader in defining cost-effective and climate-optimized, passive house and building standards. Phius certified projects are now coming in at little or no cost premium compared to conventional buildings. Phius also leads in professional training, certification, and workforce development. We also provide an element critical to mainstream adoption: Quality assurance and risk management.

The building sector accounts for 40 percent of carbon emissions, and is key to achieving emissions reduction goals. Passive house and building principles have been, and will continue to be, CORE to our efforts. In that spirit, the formerly known PHIUS+ building certifications have been renamed and expanded. 

PHIUS+ will now be referred to as Phius CORE (before renewables) and PHIUS+ Source Zero will now be Phius ZERO (based on CORE), and will extend to netting out emissions on an annual basis. New passive house and building retrofit certifications are in the offing as well. Phius CORE REVIVE and Phius ZERO REVIVE, as well as a new commercial building certification called Phius CORE COMM and Phius ZERO COMM will be introduced in 2022. 

Phius certifications have grown exponentially around the continent in recent years. Policy progress nationwide has been impressive to say the least. We are in Tarrytown, New York, for PhiusCon 2021 (formerly North American Passive House Conference) to celebrate the leadership of New York State/NYSERDA in formulating an aggressive climate action plan — a process which Phius helped inform. Other states, such as Massachusetts, have modeled their plans after New York’s. Phius’ pre- and fully certified unit count in Massachusetts over the last few years alone is impressive.

Phius Housing Units (In Process or Complete)

 

The Phius Alliance has expanded nationally, and the global network continues to grow. Phius projects have now been completed or are under way in many countries with varying climate zones. The Phius professional training has been translated into Japanese and has been taught this year successfully in Japan by Phius partner PHIJP.

The last decade was focused on figuring out the building part of the decarbonization equation (mission accomplished — solving for climate, cost, comfort). Now it’s time to expand beyond the building itself. We see Phius buildings as valuable capacitors of the new, renewable grid. They are low-load buildings that have the ability to load-shift and shed, which is immensely beneficial to the optimization of the overall grid design and resilience. 

Phius has begun to assess and measure the benefits of low-load buildings for the overall grid design, including micro and nano grid models. We call this initiative Phius GEB (Phius Grid-interactive Efficient Buildings) led by our Associate Director Lisa White. A pilot for a microgrid Phius community certification is underway. Buildings plug into the grid, and new opportunities for synergies and resilience arise. Design for the best result does not stop at the building envelope or lot line. 

Our new teal-colored logo symbolizes this expanded vision. It is a closed loop symbolizing whole systems design on all levels, aiming at harvesting adjacent system synergies: “The whole is greater than the sum of its parts.” The color teal represents clarity of thought, rejuvenation, open communication and integrity. 

Same Phius

While Phius will be steadily expanding its zero-carbon framework beyond its hallmark passive house and building standards, we will maintain our core competencies of aiding in design, building, policy writing and quality assurance. We are working to solidify and upgrade our foundational programs. Certification staff has doubled and processes are being refined. We are working on getting even better at what we already do well!

The Phius focus has evolved to the broader task of decarbonization. We’ll do so with the same scientific rigor and attention to detail as before. Our goal is the next level of systems optimization so we as a society can make real-time ZERO carbon (not just net) a reality soon!

We hope you’ll join us and continue to trust us to pave the way for the future of decarbonization strategies. There is still lots to do, so let’s get to it!

What are QAPs and Why are they so Important to Phius?

isaac picIsaac Elnecave, a member of the Phius certification team, breaks down Phius’ involvement in the Qualified Action Plans of various states, specifically Illinois and Michigan.

Over the last few weeks, Illinois and Michigan have proposed (and in the case of Michigan, finalized), the latest version of their Qualified Allocation Plans (QAP).  What is a QAP?

A good working description of the QAP can be found at the Illinois Housing Development Agency website: 

The Qualified Allocation Plan (QAP) sets forth the criteria for evaluating all projects that apply for a tax credit allocation. The QAP sets forth the rules under which the IHDA offers affordable housing development funding in the form of federal Low Income Housing Tax Credits (LIHTC). The QAP describes the selection criteria and application requirements for receiving these federal tax credits and tax-exempt bonds. 

Illinois Housing Development Agency Website

The LIHTC, a federal program administered by states, incentivizes the construction of low income housing.  States determine who receives the tax credit through the evaluation of the QAP. 

7_Harry and Jeanette Weinberg CommonsThe QAP is a points-based system. A developer submits a proposed project to the housing agency. The proposed project then receives points based on whether they achieve criteria set out in the QAP. Points can be awarded under a variety of categories such as (please note that each state has its own characteristics): 

  • Building characteristics, 
  • community characteristics, 
  • development team, 
  • financing and 
  • sustainability. 

For example, under building characteristics, a project can receive points for having an increased number of accessible units and engaging in cost containment. Under community characteristics, a project can receive points for being located near public transit. Under sustainability (the category of most interest to Phius readers), a project can receive points for meeting either energy efficiency or green building standards. 

The QAP presents a great opportunity to incentivize the construction of low-income buildings to the Phius standard. In Pennsylvania, when the Pennsylvania Housing Finance Authority awarded significant points to projects built to the Phius standard, the number of projects built to the Phius standard grew substantially.

Illinois 

In the new Illinois QAP, a project that meets the basic Phius designation — Phius CORE — would receive 10 points. If the project meets the Phius ZERO certification, it would receive an additional 3 points, for a total of 13. Thirteen points represents a significant percentage of the maximum 100 points. 

Moreover, the agency structured the point values so that a developer could meet both a green designation such as Enterprise Green Communities and Phius. This provides an additional pathway as receiving a Phius certification is one way of meeting the EGC energy designation.  

The Illinois QAP can be found here.

Michigan 

In Michigan, projects need to meet a minimum threshold requirement (such as EGC), and can receive an additional four points by achieving a Phius certification. So, much like in Illinois, Phius can work in tandem with green standards such as Enterprise Green Communities.  For example, a project that incorporates a Phius certification as part of the EGC requirements would meet the threshold requirement and receive an additional four points toward the overall score — an approach that leverages the strengths of both standards.  

The Green Standard requirements of the Michigan QAP can be found here.

Ultimately, Phius hopes to get its standard as part of the QAP in every state. Currently, there are about a dozen states, primarily in the Northeast, that incorporate Phius into their QAPs. The work in Michigan and Illinois charts a path to broadening the geographic scope of this important incentive program to help promote the construction of Phius certified low-income housing across the entire country.

Chicago Regulation Change Provides Opportunity for Phius Professionals

Al Mitchell

Al Mitchell

Phius Technical Staff Member Al Mitchell wrote this week’s blog post, which discusses the recent change in regulations related to coach houses in Chicago, and how designing these new buildings to Phius standards is a win-win for all parties.

The City of Chicago has lifted a nearly half-century ban on accessory dwelling units (ADUs), opening up a door for some people to build additional units on their property. The pilot program for ADU construction pertains to rentable units, occupiable by relatives, tenants, or even to be used as additional space from the primary home. There are two types of ADUs acknowledged by this regulation: a detached dwelling unit, such as a coach house or apartment on top of the garage, or a conversion unit, such as a built-out attic or basement.

However, there are a handful of caveats to consider. First, the allowances for ADUs, whether coach houses or conversion units, are limited to select pilot zones. There are five pilot zones: North, Northwest, West, South, and Southeast. These zones cover portions of 25 of the 77 Chicago community areas. Each area has a few special requirements for different types of ADU. For example, the North and Northwest zones can have a coach house built on the property before a primary house is built, while the other three zones require a primary house to be built on the lot before a coach house can be built. In the West, South, and Southwest zones, buildings must be owner-occupied in order to add a conversion unit. All ADUs in Chicago are to be rented for a minimum period of 1 month, and there is a requirement for a certain number of affordable units on larger properties where more units can be added.

 

Blog Pic 1This offers a great opportunity for people to add value to their property, create flexible living spaces (especially to take advantage of the benefits of multi-generational housing) or build a unit that can provide additional income for the owner while providing right-sized, cost-effective housing for another person. Approximately 70% of the lots in Chicago are 25 feet wide and face broadside south, making the applicability of this format broad. The aim of this blog is to make the case for building these newly allowed accessory dwelling units following the Phius passive building standards to create comfortable spaces, save energy and operational costs, and provide spaces that can weather inclement weather conditions, especially during a failure of space conditioning.

Analysis

Conversion units like the ones proposed in Chicago, would likely require a complete building retrofit to achieve the maximum cost and energy saving potential. This study is going to focus on detached coach houses, of maximum permitted dimensions. This comes at an apt time for Phius, as 2021 has marked the release of a user-friendly and streamlined prescriptive compliance path, as well as the performance target curves have been reworked to include allowances for small living spaces (in response to the tiny home craze).

Looking at coach house potentials, four cases were selected for evaluation. Three of the cases represent a single-story unit, one in the place of the garage, one pushed forward with open parking on the alley, and one built on top of the garage. The fourth case is a two-story coach house with no garage. The smaller units are studios, with no bedroom considered, one occupant, and the two-story coach house has one bedroom and two occupants. The standard kit of appliances is a dishwasher, refrigerator, and an induction range. Electric resistance water heaters are used in the base cases and a split heat pump system provides space conditioning.

The base cases follow code minimum constructions and windows per IECC 2018.  An envelope airtightness of 0.31 CFM50/sqft was used to match typical construction. The Phius CORE Prescriptive Path follows the prescriptive requirements per Chicago – Midway airport, and uses the default airtightness of 0.04 CFM50/sqft. The prescriptive path windows are whole window U-Values, and are set based on the required prescriptive comfort standards. Per the water heater efficiency requirements, the water heater was upgraded to a small heat pump water heater. The performance path uses 0.06 CFM50/sqft as the required airtightness metric, and follows the same window set as the prescriptive path. A heat pump water heater was used.  The other opaque assemblies were backed off from the conservative prescriptive path to meet the required calculated targets. Please reference the table below for the envelope performance specs in the study.

 

Case Wall R Roof R Slab R Window-U Airtightness CFM50/sf
IECC 2018 18.4 44.0 10.6 0.3 0.31
Phius 2021 CORE Prescriptive 40.0 71.0 21.6 0.16 0.04
Phius 2021 CORE 26.8 52.0 17.2 0.16 0.06
Blog Pic 2

 

Conclusion

The cases designed to Phius standards prove to reduce the space conditioning loads significantly, as shown in the Space Conditioning Results Chart. These outputs are specific per area, making it easy to compare different building sizes. Per the Source Energy Chart, the Prescriptive and Performance averages save 35% and 30% respectively. These source energy savings directly reflect the anticipated savings on an electrical power bill for the tenant of these coach houses.

Coach houses built to these passive building guidelines project significant energy savings that will directly benefit the occupants of these buildings, on top of the other comfort and passive survivability (what happens during a power failure – stay tuned for a part two blog). The required upgrades to meet the performance path is principally based around better windows and airtightness, saving on other insulation requirements per the prescriptive path. 

Blog Pic 3

The Phius Difference: Custom Energy Design Targets for Heating and Cooling — The Key to Zero

Katrin Klingenberg -- Co-Founder & Executive Director, Phius (Passive House Institute US)

Katrin Klingenberg — Co-Founder & Executive Director, Phius (Passive House Institute US)

The Klingenblog’s namesake, Katrin Klingenberg, wrote this week’s blog, examining custom energy design targets and how Phius’ approach to them sets the organization apart in the quest for Zero.

Designing zero energy and zero carbon buildings today can be cost effective if guided by the appropriate targets for investment in efficiency first. These targets are cost-optimized limits on heating and cooling loads.

The limits on heating and cooling loads are set to guide the design to a cost-optimal investment in passive conservation strategies: insulation (the appropriate amount, properly installed), dedicated continuous air, water, and vapor control layers, mitigation and avoidance of thermal bridging, high-performance windows (with appropriately tuned solar gain) and dedicated balanced ventilation with filtration and energy recovery. These principles ensure building resilience, health, comfort, safety and durability.

The cost optimization to set the targets focused on achieving the highest source energy savings (relative to a code baseline) for the least total cost (including the up-front cost of energy-saving measures, and ongoing operational costs). It factors in the cost of materials and the cost of energy supply in each particular region to calculate the sweet-spot. At some point, up-front conservation measures don’t pencil, and that’s when any additional investment should shift to active conservation strategies or active renewable energy generation systems.  These climate-optimized, project-specific targets for thermal performance define the cost-effective sweet spot on the path to zero.

The thermal performance targets are known in the industry as “Annual Heating Demand” and “Annual Cooling Demand.” They are expressed in kBTU per square foot per year or — in the metric world — in kWh per square meter per year. They are, in concept, similar to the Energy Use Intensity (EUI), but refer to the delivered heating and cooling energy required by the building. These annual space conditioning demands can only be met with passive measures and dial in the thermal performance of the building. Once those are met, a conservation-first focused total energy budget is set to guide investment in active measures. This limit is also project-specific, and can be expressed in the EUI we are all familiar with — the amount of energy used by a building per unit of floor area per year, including space conditioning and all other energy uses. That EUI can be converted into an emissions equivalent as needed to determine offsets needed to achieve zero carbon. Voila! It’s that easy!

Phius is the only building certification program that has developed such design and certification targets. They are available on the Phius website in an easy-to-use calculator. Choose climate, enter building square footage and occupancy, and you get your optimized design parameters! They are also built into the easy-to-use design and certification tool, WUFI(R)  Passive.

Before supercomputing, managing such a complex, dynamic system of variables to generate custom targets as a designer was impossible. The task of energy optimization was handled by specialized engineering firms doing the modeling — a costly and external process. Small budget projects such as single-family and small multifamily projects could not take advantage of it. Even larger projects often took the prescriptive path to eliminate the cost of custom optimization. 

Today, the reliable and detailed accounting of emissions in the building sector is necessary on a per-building basis. Many cities have passed climate action plans with extremely specific emissions reduction targets to meet over the next few decades. The Phius standard now provides an easy-to-apply, cost-effective design, and certification methodology alongside accurate accounting of carbon emissions for any building in the building sector.

With some training, architects can now easily perform these calculations themselves and build it into their design workflows right from the beginning, making sure their design is on track from start to finish.

The framework for the Phius standard today was conceived in 2015, updated in 2018, and refined again in 2021. Many municipalities have leaned on and incentivized the Phius framework to meet their climate action plans. At the forefront was New York State Energy Research and Development Authority (NYSERDA) in the State of NY. They designed a proof-of-concept program early on called Buildings of Excellence. The agency now offers cost and performance data for representative groups of completed projects using varying techniques for low energy design and accounting.

C3RRO, a third-party consulting firm under the leadership of Florian Antretter, has graphed the NYSERDA cost and measured performance data for various approaches and graciously made it available to Phius for publication. The results are proving the concept. 

Graph

As envisioned, the Phius Standard, design, and certification methodology has led to projects that not only perform the best, but are also constructed at minimal additional upfront cost. (PHI projects that use a single target for heating and cooling limits in all climates also perform reasonably well but are more expensive to build).

The new comprehensive guidebook explaining the Phius Standard design and certification methodology is now available here.

We are well on our way to (Phius) ZERO emissions!