Step 3: Assess, Prioritize and Define the Sustainability Opportunity

At a portfolio level, the Sustainability Project Lead and his or her team need to gather and analyze building-specific data to assess the overall opportunities for sustainability and prioritize the investments to be made across the portfolio. These steps are a comprehensive approach to assess sustainability:

  1. Assess individual building opportunities
  2. Prioritize specific buildings
  3. Establish portfolio building targets and build sustainability business case
  4. Obtain leadership commitments

Assess individual building opportunities.

Assessments should be completed by knowledgeable individuals using one of the following three approaches: 

  • Comparing aggregate energy usage on square footage basis across buildings (simplest and least thorough)
  • Using third-party benchmark or assessment tools (often online) to assess building opportunities
  • Completing an ASHRAE Level II building audit, a standard set by the American Society of Heating, Refrigerating and Air Conditioning Engineers (very thorough)

The following chart illustrates the range of approaches available to assess building sustainability opportunities and lists their respective benefits and limitations. (Approaches on the left; those on the right cost more but provide far more information, and are generally worth the investment.)



  • Inexpensive, simple to perform.
  • Divides annual energy consumption from review of utility bills or online utility tool by the building’s square footage.
  • Provides a relative comparison of buildings across a portfolio and can show buildings that have deteriorating performance over time.
  • May be good for identifying a building with high potential where some early wins could be established.
  • Typically inexpensive and can be done remotely.
  • Many can show performance relative to peers.
  • Some tools are more thorough than others. For example, New Buildings Institute’s (NBI) FirstView tool allows comparison across a portfolio of buildings.
  • ENERGY STAR™ Portfolio Manager or LEED® provide highly comparable benchmark scores
  • Extremely detailed and accurate.
  • Sizes the opportunity unique to the building and provides specific recommended measures to consider for implementation.
  • Typically, done by an independent third party who may be more apt to identify all opportunities.
  • See description of ASRAE level audits here.




  • The metric only provides a rough approximation of potential opportunities. Many, often legitimate, factors influence this metric. For example, presence of a data center, hours of operation or a changing occupancy % can skew results. This approach does not assess non-energy sustainability opportunities.
    • Most benchmarks and tools are limited in their ability to size specific opportunities.
      • May require payment to an external engineer to perform work if internal resources are not qualified. Internal resources may be less likely to identify opportunities with which they may be unfamiliar.


        Prioritize specific buildings.

        In addition to cost-effectiveness, consider business objectives, building requirements and the current real estate portfolio when prioritizing buildings. Consider the following factors:

        Prioritize specific buildings.

        The Portfolio Assessment Tool can help the Sustainability Program Lead compare and aggregate the portfolio opportunity and identify the individual opportunities that best align to portfolio goals.

        Establish portfolio building targets and build the sustainability business case.

        Depending on the size of the organization, it may be necessary to create a formal business case to gain senior management buy-in for implementing the sustainability measures.

        To do this, the Sustainability Project Lead should:

        • Quantify the sustainability opportunity by property and show the reasons for prioritizing certain buildings
        • Include criteria on available dollars for investment, expected returns, and other upsides to the portfolio
        • Ensure that the improvements are not operational in nature, and then that the sustainability business plan aligns with building capital budget schedules wherever possible

        Some organizations may require more detail before selecting buildings to prioritize. Step 5 addresses the process to generate Building Actions Plans for individual buildings.

        Establish portfolio building targets and build the sustainability business case.

        While the Portfolio Sustainability Program should have a plan that assures some early success, the bigger picture will likely include longer payback initiatives. The Sustainability Program Lead should consider bundling a few improvement efforts together to achieve the portfolio’s target payback or required ROI (e.g., combining relatively quick payback lighting replacement projects with sustainability efforts such as buying recycling or composting containers). By doing so, the sustainability effort could gain more LEED points and still meet portfolio investment criteria.

        The business case should also address accelerated replacement of larger capital items (e.g., replacing current air conditioning with more efficient units; end-of-life can prove to be a positive investment for each building).

        Obtain leadership commitments.

        The Sustainability Project Lead should develop the business case for sustainability and receive buy-in from the Sustainability Champion. The Sustainability Champion should, in turn help to obtain buy-in from other members of senior management. To a large degree, senior management will determine the scale and success of the Portfolio Sustainability Program, as they control resources and funding.

        It is also helpful to educate senior management on the benefits and potential impacts of the Portfolio Sustainability Program, driving them to continue to prioritize sustainability on an ongoing basis.

        Property and Building Managers should create onsite building sustainability teams to implement the Portfolio Sustainability Program as it relates to their individual buildings. Property and Building Managers and the Sustainability Program Lead should consider that Sustainability Program implementation will likely layer on top of the building staffs’ regular responsibilities, and so they should set expectations accordingly and address each of their concerns to gain full commitment.

        The Property/Building Managers should explain the goals and objectives and how the Portfolio Sustainability Program will:

        • Improve overall operations
        • Help the organization save money
        • Increase tenant satisfaction (and they should offer examples of how to properly communicate with and engage tenants)

        Next: Establish performance measurements >