Sustainability

Navigating Resilient Infrastructure Design with LEED v5: Building a Sustainable Future

By: Elizabeth Arsenault, Sustainability Consultant; Andrew Kang, Sustainability Manager

Building for Tomorrow: The Rise of Resilience in Sustainable Design:

In today’s ever-changing landscape, resilience has emerged as an essential concept, especially within the built environment. Defined by the U.S. Green Building Council (USGBC), as the ability to prepare and plan for, absorb, recover from, and more successfully adapt to adverse events, resilience has become a cornerstone in the discourse of sustainable development.

The urgency of resilient design is further highlighted by the World Economic Forum’s 2024 Global Risks Report, where five of the top ten global risks are identified as directly related to environmental factors.

As our infrastructure faces increasing environmental pressures from these risks, the need for resilient construction becomes imperative. In response, the USGBC places an emphasis on resilience in the latest iteration of the Leadership in Energy and Environmental Design (LEED) rating system, v5.

Please note, the information conveyed in this blog is based on the piloted version of LEED v5 BD+C NC and is subject to refinement prior to being released for registration and use.

Integrative Process Prerequisite: Climate Resilience Assessment:

The first incorporation of resiliency in LEED v5 BD+C NC (Building Design and Construction, New Construction) is the Integrative Process Prerequisite: Climate Resilience Assessment. In short, this prerequisite requires the project team to complete a comprehensive assessment for climate resilience, aiming to increase awareness of hazards and risks, but does not require follow-up actions. Moreover, the requirements include identifying and evaluating current and potential future natural hazards relevant to the project site and its operations. Once these hazards are identified, the assessment must outline their impact on the project’s planning, design, operations, and maintenance. Additionally, the assessment should explore ways to enhance the project’s resilience to these environmental stressors. If any identified hazards do not apply to the project site, justification for their exclusion should be provided.

Impacts to the project team will include efforts during the early design phase to assemble the Climate Resilience Assessment. These proactive measures lay the groundwork for developing infrastructure capable of withstanding a range of climate and weather-related challenges.

Site Selection Prerequisite, Resilient Site Design:

The next mention of resiliency in the LEED BD+C v5 NC framework is the Site Selection Prerequisite, Resilient Site Design. Put simply, this prerequisite reduces flooding risk by either  imposing development location requirements or by implementing relevant flooding management tools and systems.

More specifically, its purpose is to design and build critical utilities—such as electrical, HVAC, communications, wastewater systems, and backup power/generators— to withstand against flood events up to the 500-year floodplain level by adhering to at least one of the following requirements:

  • Locate critical utilities at or above the 500-year floodplain level. If unable to determine due to data limitations, implement flood-resistant design measures based on best available information.
  • Incorporate critical utilities within protective flood-proofed enclosures.
  • Implement best management techniques, including elevated foundations, flood barriers, waterproofing materials, green infrastructure, and flood vents, considering topography, rainfall patterns, and potential flooding sources.

https://gismaps.kingcounty.gov/iMap/

This prerequisite requires additional effort from the project team, as it may influence the selection of the project site and/or design strategies. For owners and developers intending to integrate LEED into future projects, these factors are great to consider early on, preferably before site selection. However, for projects with pre-determined locations, the design team can integrate flooding management tools and systems into the project’s design during the early stages of development. These flooding mitigation methods offer owners and property managers a cost-effective solution to reduce spending on critical utility repairs.

Sustainable Sites: Credit: Enhanced Resilient Site Design

The Sustainable Sites: Credit: Enhanced Resilient Site Design is the first optional resiliency measure in the LEED v5 BD+C NC framework, offering projects a chance to showcase their dedication to exceeding standard requirements.

Building upon the groundwork laid by the Integrative Process Prerequisite: Climate Resilience Assessment, this credit mandates the project team to choose at least two of the highest priority environmental hazards and implement the corresponding LEED Enhanced Resilience best practices to mitigate climate threats. Furthermore, it provides multiple pathways of pursuit, offering flexibility to the design team while also ensuring the incorporation of resilience measures that surpass industry standards.

To achieve optimal success and cost efficiency, the project team should adopt an integrative approach by considering these measures in the early design phases. Incorporating enhanced resiliency measures during this stage bolsters the longevity and performance of buildings, thereby strengthening owners’ portfolios and reducing repair and restoration costs.

[Top] Iron Bridge – Paving materials with an initial solar reflectance (SR) value of at least 0.33 used to mitigate extreme heat [Bottom] Liza – Shaded external spaces adjacent to buildings for use during extreme heat events.

Indoor Environmental Quality Credit Resilient Spaces:

The final credit related to resilient buildings is the Indoor Enviromental Quality Credit Resilient Spaces. This unique credit enhances occupants’ ability to adapt to changing climate conditions and protects them from events that may compromise the quality of indoor spaces, thereby positively impacting their health and well-being.

Similar to the Sustainable Sites Credit: Enhanced Resilience, the Resilient Spaces credit offers a handful of pursuit options, providing flexibility to select the path that best aligns with the project’s location or predetermined design. This acknowledges the project team’s commitment to advancing resiliency measures beyond the norm, reflecting a level of dedication that sets them apart.

Pursuit options available to the project team include:

  • Management Mode for Episodic Outdoor Ambient Conditions: Design a system capable of addressing varying outdoor conditions or events, such as wildfire smoke, that may negatively affect indoor air quality.
  • Management Mode for Respiratory Diseases: Design occupied spaces capable of operating an Infection Risk Management mode, meeting minimum clean airflow rates outlined in ASHRAE 241-2023 section 5.1.
  • Management Mode for Power Outages: Design the project to maintain habitable temperatures during power outages.
  • Operable Windows: Incorporate operable windows in 75% of regularly occupied spaces.
  • Building Safety: Design for one high-priority hazard identified in the Climate Resilience Assessment Prerequisite.

These measures are most effectively integrated when considered in the early design stages, offering significant added value through occupant comfort, well-being, and safety.

Embracing Resilience: Paving the Way for a Sustainable Future with LEED v5:

Integrating resiliency measures into infrastructure design offers many benefits. It enhances a building’s ability to endure and adapt to adverse conditions, ensuring its continued operation and success. Additionally, it brings tangible benefits to both owners and tenants, fostering a sense of security and promoting occupant health. Lastly, it aligns closely with many organizations’ existing sustainability goals by prolonging the lifespan of existing structures and minimizing the need for additional construction, thereby reducing future embodied carbon emissions. Prioritizing resilience in infrastructure design not only strengthens our built environment but also paves the way for a more sustainable and resilient future.

If you’re interested in learning more about resiliency or would like to collaborate on a project, our team is here to support you. Contact us today to explore how we can work together on your next project.