by Jesse Walton

In 2020, I co-authored a blog post that showcased Mahlum’s history of incorporating sustainable strategies into our work and our prioritization of performance in pursuit of carbon neutral buildings in alignment with our participation in the AIA 2030 Commitment. That post stated, “We now have measurable data that shows us where we are in relation to the goals of the AIA 2030 Commitment, and how much further we must go to get there. In the past four years through methodical collection of pEUI, operational, and embodied carbon data I have come to the realization that there is uncertainty if we will achieve net-zero emissions by 2030. I hesitate to publicly acknowledge this potential failure; but as we look at the realities of our industry’s impact on our current climate emergency, we need to be honest with ourselves now more than ever. In the spirit of transparency, I invite you to learn why I think we will most likely not achieve net-zero emissions by 2030 and how we will push through this uncertainty.

Mahlum has a current pEUI reduction of 67% which is well above the AIA 2030 signatory firm average of 48%. While our progress has steadily been tracking towards net-zero energy we need to improve by ~5% annually to reach net-zero and our recent progress is only ~3%, highlighting that success is far from guaranteed.

Below are four endemic reasons why I believe we (and other firms) may not reach the intended target by 2030, but I also share why (and how) Mahlum continues to push our work to make our buildings low-carbon.

REASON 1: Energy Codes Are Not Stringent Enough
Many of Mahlum’s projects go above and beyond the energy code prescriptive minimums, but most of our work is at or very close to the minimum energy code requirements. Without more progressive codes that require 80%+ energy reductions and also mandate renewables, our work on average will not achieve net-zero emissions. Some energy codes in the US have pushed past 60% reduction from the CBECS 2003 Baseline but the vast majority are well below a level required to achieve the current AIA 2030 Commitment target of 80%. The US DOE Building Energy Code Program: Status of State Energy Code Adoption shows that most states do not adopt the latest energy code which all but guarantees nationally the building industry will not meet the lofty goals of the AIA 2030 Commitment as most buildings are built to the state or local code prescriptive minimum requirements.

REASON 2: Net-Zero Operational Carbon is Complex
Operational and avoided emissions from renewables are measured differently by different stakeholders in our industry and there is no single method of calculating your operational emissions. Depending on the methodology, tool, or story you are trying to tell, the numbers can be very different.

Some firms use the Energy Star Portfolio Manager Technical Reference on GHG Emissions, others use ASHRAE 228, and others use professional judgment on which historic emissions rates from the eGrid Data Explorer make most sense, e.g. Sub-Regions, State, or Power Plant. Then there is the time-frame in which you measure emissions. We are used to thinking about energy in building operations in a per year time-frame but emission rates change hourly and over years so you can estimate very different operating emissions if you are using historic annual “Average Emissions” or the predictive hourly “Long-run Marginal Emissions Rates” as estimated in the NREL Cambium Scenario Viewer. The White House (Biden Administration) has also recently dipped it’s toe into the debate about operating emissions in its RFI for a National Definition of a Zero Emissions Building.


REASON 3: Embodied Carbon Accounting is Nascent
The general public and AEC professionals alike have been trained to think about buildings and their impacts on the planet as an energy efficiency issue when in fact the impact comes from the emissions created from the building’s whole life cycle. Construction, renovation, and demolition of a building, often called “Embodied Carbon” has a significant impact in comparison to the operational emissions. In fact, a recent CLF (Carbon Leadership Forum) study finds the emissions generated from constructing a building are often greater than operating it over its lifetime.

The tools currently available make it easier for designers to quantify our decisions on low-carbon design but the data is still being created and collected for many scopes of work. We applaud the work in the structural design and construction industry to address their high carbon impact materials like concrete and steel with more availability of EPD’s (Environmental Product Declarations) but quantifying other building elements like MEP systems, casework, finishes, landscape, and construction activities are still in early development.

REASON 4: Carbon Offsets Are Questionable
Offsetting energy to get to net-zero energy is a relatively simple calculation: 100kWh of use minus 100kWh of production equals net-zero energy. Offsetting operational emissions by calculating avoided emissions is more complex (see Reason 2 above), and assurance of high quality global Embodied Carbon offsets is almost magical thinking.

For example, in 2019, Mahlum offset the 90mt of embodied carbon we emitted when renovating our new Portland office with a $1,600 Green-e Certified carbon offset to ensure we would achieve Living Building Challenge (LBC) Materials Petal certification. While this was technically responsible on our part, the low cost of this carbon offset (<$20/mt) still varies greatly from the US EPA Social Cost of Carbon at >$150/mt in 2030, which would have put our Portland office carbon offsets cost at $14,000.

The LMN Path to Zero Carbon said it beautifully, “To be blunt, many offset programs fail to meet many basic criteria that align with carbon neutrality goals, which is why some are so inexpensive.” I hope the voluntary and compliance carbon offset markets mature so it becomes simpler for the AEC industry and building owners to be assured that their purchased carbon offsets are high-quality and less questionable.

In spite of everything outlined above, the fact is that Mahlum will keep pushing to make low-carbon design a reality. We will:

1. Continue to measure, synthesize, and share our energy, operational, and embodied emissions annually with the AIA 2030 Commitment and other partnerships like the CLF Benchmarking Study v2. This will keep us honest about where we are in relation to our low-carbon goals and contribute to the industry’s growth and knowledge.

2. Continue our culture of design, education, and volunteerism around low-carbon buildings but acknowledge that the ways we measure and achieve these goals is nascent and evolving.

3. Update our Sustainability Action Plan (SAP) in relation to our Vision and Values. Currently our SAP is an addendum to Mahlum’s Vision and Values as they were not created at the same time but considering the current climate emergency they should be unified.

4. Help simplify the data visualization process for the AIA 2030 Commitment community by freely sharing the Tableau Public Low Carbon Design Dashboards we’ve been developing. We hope our pEUI, Operational, and Embodied Carbon visualizations help firms explore their AIA 2030 Commitment data and find meaningful trends and areas of improvement. Mahlum’s Low-Carbon Design Dashboard is now available here (and is shown as a screenshot below) for any AIA 2030 Commitment signatory to use with their firm’s DDx data export.


Thank you to Mahlum’s 2030 “Birddogs” who work diligently with our project teams to collect 2030 data; to Michelle Amt at VMDO and Dan Stine at Lake Flato for beta testing our Low Carbon Dashboards; and to Jack Rusk at EHDD for his help with the operational emissions calculations. 2030 or bust!