Best Practices for Delivering Deep Energy & Carbon Reduction Upgrades

Reusing an existing building vs demolish/build new, is the first step toward sustainability. To get to net zero carbon from existing buildings, we must go beyond changing light bulbs and upgrading HVAC.  Building Owners & Design Teams must deliver deep reductions in building energy demand and carbon emissions (both embodied and operating) using strategies like whole building ecology and bundling of measures.  There is a strong business case for doing so.  This session will explore best practices for deep green building rehab solutions that can scale, and challenge attendees to advance these practices to “standard”.

Session Notes by Eden Brukman

As session moderator, Mark Thompson Brandt captured the significance of intentional and effective building retrofits with a simple declaration: Over the next ten years, 34% of construction dollars in the US will be attributed to new buildings, 66% to existing building rehabilitation. For years 11-20, the focus on rehabilitation is projected to be even more extreme, accounting for 80-90% of construction dollars. (source: Architect magazine)

The session panelists provided additional context for understanding and addressing the weight of our existing building stock. Ralph Dinola offered guidelines, followed by case studies from Rod Yeoh and Paula McEvoy.

One key takeaway from Ralph was New Buildings Institute’s “Four steps to get existing buildings zero energy ready”:

  • Process. Make the commitment, measure and track, identify immediate opportunities and plan.
  • People. Educate everyone, engage operators and occupants, socialize low energy.
  • Practices: Reduce internal loads, start with passive strategies.
  • Products. Leverage technologies (controls, high performance systems – LEDs/glazing/HVAC).

Ralph also mapped a range of interventions to focus decision making, from Low (e.g., retro-commissioning), to Medium (e.g., envelope upgrades – adding insulation) and High (e.g., system replacement).

Rod Yeoh’s case studies included three renovations of federal buildings in Canada, which resulted in 60-80% energy savings and 75-80% GHG reductions. DIALOG modeled four scenarios to inform their client’s decision making:

  1. Compliance with minimum departmental standards
  2. Energy efficiency measures that were cost neutral from a lifecycle cost perspective over 25 years
  3. “Shoot for the stars” measures to maximize impact regardless of cost
  4. Balanced combination of measures from options 2 and 3 to maximize carbon reductions and accounting from a life cycle cost perspective
  5. Implemented strategies were straightforward, such as envelope upgrades (wall/roof insulation to increase R-value, triple-pane glazing) and mechanical system upgrades (dedicated outside air system, heat recovery, variable refrigerant flow, radiant heat).

For the MacKimmie Block and Tower Redevelopment project at the University of Calgary, DIALOG’s design interventions drew from solar and climate analyses. They included a double façade, natural ventilation, night flushing (due to high diurnal swing), use of thermal mass, and evaporative cooling.

Next, Paula McEvoy shared two substantial renovations by Perkins + Will in Atlanta, GA, both of which retained structural components but replaced most of the other elements. The Perkins + Will Offices and Interface Global Headquarters projects both resulted in major source energy reductions (58-68%) by limiting solar heat gain, using BEKA Mats for radiant heat/cooling, lighting and controls, rooftop tri-gen plant, onsite photovoltaics, and (re)commissioning.

The Interface Global Headquarters also has an impressive water story, using a 15,000 gallon cistern for treated but nonpotable water to serve flush fixtures and irrigation. The visibility of the cistern contributed to the education of the occupants as part of a robust change management plan.

For their own offices, Perkins + Will honored the existing materials and associated embodied carbon impacts. They worked with the Lifecycle Building Center to deconstruct, palettize, and inventory the materials, and then the list was published for local NGOs to claim items for reuse. Materials were rehomed instead of landfilled. Another way that Perkins + Will reduced per capita operational and embodied carbon was to shift workplace expectations – they reevaluated individual space and stuff, ultimately leading to a reconfigured layout that allowed leasing space to a third tenant. 

In closing, Mark briefly shared a case study by MTBA Associates of a historic project. On the Sir John A MacDonald Building, they reused the green roof, and added insulation, lighting/sensors, water conserving fixtures, automated building control systems, and new HVAC – all with the intent to leverage the building components’ dynamic relationships and inherently sustainable features.

Noted Resources:

Session Lead: Mark Brandt, Zero Net Carbon Collaborative

Mark Thompson Brandt is Principal Conservation Architect & Urbanist at MTBA Associates, with over 30 years’ experience. Former Director of Canadian Association of Heritage Professionals and of Canada Green Building Council /Ottawa, Mark is a Director of APT, the Association for Preservation Technology International, Co-Chairing APT’s Technical Committee on Sustainable Preservation. He is the founding Co-Chair of ZNCC, the Zero Net Carbon Collaboration for Existing & Historic Buildings. Brandt is co-author of the national document “Building Resilience: Practical Guidelines for the Sustainable Rehabilitation of Buildings in Canada”. Parliament Hill projects include $70M East Block Rehabilitation and $100M Sir John A. Macdonald Building, which received 7 National/International awards and 5-Green Globes rating. 


Ralph DiNola is an expert facilitator and convener providing inspiration and a pathway for business, policymakers and building owners seeking quantum advances in building energy performance. Ralph has dedicated his professional life to bringing sustainability, green building and energy efficiency innovation to scale. For more than 20 years he has served as a consultant to developers, governments and Fortune 500 companies seeking quantum advances in their building practices and projects. He has been invited to provide keynote presentations at corporate meetings and international conferences and serves as an expert facilitator and educator. Ralph served as a technical advisor for the Living Building Challenge™ standard and has consulted on over 130 LEED® projects, including ten precedent-setting LEED Platinum certifications. Ralph was founding Board Chair of the International Living Future Institute, served on the USGBC LEED Retail Committee and was recipient of the Better Bricks Green Building Advocate Award and voted one of the 50 most influential Portlanders by Portland Monthly Magazine. Ralph has a bachelor’s degree in Historic Preservation from Roger Williams University and a Master’s Degree in Architecture from University of Oregon. The New Buildings Institute is known internationally as a leader in the field.

Rod Yeoh is widely acknowledged as a leader in integrated practice development and project management, Rod brings over 24 years of international experience in a broad range of project types to the firm. His past success with multi-disciplinary design and delivery build on the leadership and growth of DIALOG’s integrated practice.The success in Rod’s collaborative approach is exemplified by a portfolio of sustainable, high-performance buildings. These include the award winning City of Vancouver National Avenue Works Yard, the first building to be LEED certified by the CaGBC, the Fred Kaiser Engineering Building at UBC acclaimed for its energy efficiency and several BC Hydro field operations facilities designed to meet LEED Gold and Platinum equivalents.

As Co-director of Perkins+Will’s firmwide Sustainable Design Initiative (SDI), Paula McEvoy assures that sustainable ideas are an integral part of the firm’s projects and practices. She coordinates sustainability efforts across the international firm’s offices, teaches sustainable design workshops and speaks frequently on sustainable construction, business practices and visioning. She has been instrumental in defining sustainability at Perkins+Will and has been directly responsible for shaping the firm’s commitment to leadership in sustainable design. A Registered Architect and LEED® Fellow, Paula has the type of exemplary, broad-based experience that generates a unique, holistic approach to her work. Paula has been Project Architect for a wide variety of projects, with a focus on sustainable, high-performance buildings. She is a member of The American Institute of Architects and 2010 President of AIA Atlanta. In addition, she is USGBC LEED Faculty, and serves on the Board of USGBC Georgia Chapter.