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Cliff Notes for GRESB: What’s New in Performance Indicators

A new and substantially different version of GRESB’s Performance Indicators aspect has landed. So toss out your old spreadsheet (it won’t help this year), pull out your copy of the GHG Protocol, and get ready to rethink your approach to this important aspect of GRESB!

First, why the change? The new Performance Indicators (PI) aspect has been overhauled in an attempt to make it clearer, better reflect the reporting realities of GRESB’s diverse respondents, and accommodate feedback from stakeholders. While the market absorbs the changes, we can try to get in front of them to understand what’s being asked of us and how best to respond. We’ll start with a quick scan of the new PI aspect. It reveals some familiar terms such as “Like-for-Like” and “Consumption,” as well as a lot of new ones like “Energy Intensity,” “Data Coverage,” “Base Building,” and “Indirectly Managed Assets.” Here’s a look these new concepts and some thoughts on how to address them:

Data Coverage: This is the percentage of portfolio floor area on which you’re reporting. For example, if you know energy consumption for 100,000 square feet out of a 1,000,000 square foot office portfolio, your data coverage is 10%. Simple, right? Not so fast! To get this right, you’ll need to calculate data coverage for every asset by either (a) base building and tenant spaces OR (b) by whole building. If you elect to go the base building/tenant route, you’ll have to allocate individual meters according to who pays the bills for each. When you’re done, aggregate all asset level data for each property type in your portfolio…or just sync your data in Measurabl and let us handle it all for you!

Why Data Coverage Is Important: Data coverage is a HUGE driver of your overall score. Simply put, the more of your portfolio for which you state energy, carbon and water performance (waste is the sole exception to the data coverage phenomena), the better.

Optional Data Coverage: This is intended for reporters who state portfolio size in “units” or “lettable” (aka rentable) area. If you stick to reporting in good old fashioned square feet or meters, you can ignore columns E & F entirely. Phew!

Why Optional Data Coverage Is Important: Occasionally, the size of real estate holdings is reported using denominators other than square feet. For example, hospitality and residential property types are frequently described by the number of “units” in their portfolio. Using this option when square footage is not available may be convenient.

Intensity: Absolute consumption of energy or water is an all but useless abstraction. The only way to compare the consumption/output of one portfolio with another is to normalize it according to some common denominator. Normalizing helps us compare performance across different portfolios. So if Portfolio A uses 1.2 kWh and Portfolio B uses 2.5 kWh, respectively, per square foot per year, we’re in a position to say something more meaningful given the size of the overall portfolio. The good news about intensity calculations is you have flexibility about which normalizer (“denominator”) you use. We suggest a basic formula of: (Total Usage  for One Year / Total Square Feet).  You’ll notice this is the identical formula applied by ENERGY STAR Portfolio Manager to get Energy Use Intensity (EUI). In GRESB, you’ll need to calculate intensity for each property type (or let Measurabl do it for you!). One of the drawbacks of allowing so much discretion over intensity figures are calculated is that variances in calculation methodologies may result in diminished data comparability from one respondent to the next.

Why Intensity Is Important: Intensity figures give an “apples-to-apples” view of energy, carbon, water or waste consumption/output across buildings and portfolios of different sizes, geographic distribution and composition.

Indirectly Managed Assets: These are assets where a single large tenant “runs the show” in that you do not have  authority to introduce policy or operating changes to an asset. Instead, that’s the tenant’s prerogative. This should be easy to spot. Just look for any building where the lease structure explicitly devolves responsibility for day-to-day operations, maintenance or enforcement of environmental policies to a single large tenant. Where that’s the case, report the asset as indirectly managed.

The concept of reporting on indirectly managed assets is a somewhat unusual requirement for a standard based on the principal of “Operational Control.” Operational Control means you report on the assets over which you exercise “day-to-day authority”—all 100% of the asset, not just the amount proportional to your economic interest (that’s a different reporting concept called “Financial Control”). For GRESB’s purposes, we recommend doing your best to report on indirectly managed assets, but rest assured GRESB understands this is a difficult group of assets on which to collect data.

Why Indirectly Managed Assets Are Important: This allows GRESB to distinguish between those assets where you have real ability to influence performance, and therefore should be held accountable for environmental outcomes, versus those where you do not.

We hope this sheds light on some of the trickier concepts in GRESB’s new 2014 Performance Indicators aspect. We’ll dig into how to properly allocate tenant meters and some of the other intricacies of GRESB in forthcoming blogs. In the meantime, we’d love to hear from you about how you’re handling these calculations—send us an email at Thanks!