How to Benchmark a Multi-Tenant Commercial Building
Energy benchmarking is relatively straightforward when a building owner receives all of the utility bills for a property.
Multi-tenant buildings, however, can be very different.
The owner may pay for common-area electricity and central HVAC, while individual tenants pay their own electric or gas bills. Some suites may have dedicated utility meters. Others may share meters. Tenants move in and out, utility accounts change, and a building owner may never see a large portion of the property's actual energy consumption.
That creates one of the most common challenges in multi -tenant building energy benchmarking:
How do you accurately benchmark the whole building when you do not pay, or even see, all of its utility bills?
The answer starts with understanding the difference between owner-paid utilities and whole-building energy use.
Benchmarking Should Represent the Whole Building
Energy benchmarking is intended to measure how the property performs as a whole.
That means the goal is generally not to enter only the energy appearing on the owner's utility bills.
Imagine a 100,000-square-foot office building.
The owner pays for:
Lobby and hallway lighting
Elevators
Exterior lighting
Central HVAC equipment
Common-area electrical loads
Individual tenants separately pay for electricity inside their offices.
If the owner benchmarks only the accounts they pay directly, a significant amount of tenant energy use may be missing from the utility data.
The resulting Energy Use Intensity, or EUI, could make the property appear to use substantially less energy than it actually does.
Before beginning multi-tenant building energy benchmarking, owners should therefore ask:
Does our data represent the entire building, or only the utilities we pay for?
Start by Mapping Every Utility Meter
Before collecting data, create an inventory of the meters serving the property.
For each energy source, identify:
Utility provider
Meter or account number
What area the meter serves
Whether the owner or tenant pays the bill
Whether the meter is active
Whether any meters have been added or removed
Whether common areas have separate meters
Do this for electricity, natural gas, and other applicable fuel sources.
A meter inventory helps prevent one of the easiest benchmarking mistakes: assuming the utility accounts in the owner's accounting system represent the entire property.
Owner-Paid vs. Tenant-Paid Utility Data
Owner-paid utility data is usually the easiest information to collect because the property manager already receives the bills.
Tenant-paid energy can be more complicated.
Depending on the property and utility, there may be several ways to obtain the missing consumption information.
One option is collecting utility data directly from individual tenants. This can work in smaller buildings, but it becomes difficult when lots of accounts are involved.
It also creates an ongoing administrative challenge. Every time a tenant changes, the utility account may change too.
Another option may be aggregated whole-building utility data.
What Is Aggregated Utility Data?
Aggregated data combines energy consumption from multiple meters or accounts into a whole-building total.
Instead of receiving individual Tenant A, Tenant B, and Tenant C utility records, the building owner may receive a combined consumption figure for the property.
Where utilities offer this service, it can simplify multi-tenant benchmarking significantly.
Aggregated data can also help address tenant privacy concerns because the owner may not need access to each tenant's individual bill.
Availability, eligibility requirements, authorization procedures, aggregation thresholds, and delivery methods vary by utility.
Some utilities can transfer aggregated data directly into ENERGY STAR Portfolio Manager. Others provide files that must be entered or uploaded separately.
The important point is that building owners should not assume tenant-paid utilities are unavailable simply because they do not receive the bills.
Contact the serving utility and determine what whole-building data options are available.
Utility Authorization Can Take Time
Obtaining tenant or aggregated utility data is one reason multi-tenant benchmarking should not begin a few days before a compliance deadline.
Utilities may require:
Owner verification
Account information
Authorization forms
Proof of ownership or management authority
Tenant authorization in some circumstances
Enrollment in an automated data service
The exact process varies.
If information is incomplete or an authorization is rejected, resolving the issue may take additional time.
For buildings subject to annual benchmarking requirements, completing utility authorizations well before the filing deadline can prevent an unnecessary last-minute scramble.
Do Not Forget Common Areas
Tenant meters receive a lot of attention, but common-area meters can be missed too.
A commercial property may have separate accounts serving:
Parking garages
Exterior lighting
Elevators
Central plants
Cooling towers
Common-area HVAC
Corridors and lobbies
Shared amenities
Those loads are still part of the building's energy use.
For example, an office tower could have complete tenant electricity data but accidentally omit the meter serving its central HVAC plant.
The benchmarking record would technically contain plenty of data, but it would not accurately represent the property's actual consumption.
Completeness matters as much as quantity.
Look for Missing Months and Data Gaps
Once all relevant meters have been identified, review the reporting period for gaps.
Benchmarking commonly relies on a complete 12-month period of utility consumption.
Look for:
Missing months
Duplicate bills
Overlapping meter entries
Estimated readings
Meter replacements
Accounts that began or ended midyear
Unexpected zero-usage periods
Large unexplained changes
Tenant turnover can make this especially tricky.
A suite may have one utility account for the first six months of the year and a completely different account after a new tenant moves in.
If the old meter history disappears from the data collection process, the property could end up with an incomplete year.
Verify the Building Information Too
Accurate utility data is only half of good benchmarking.
The property information in ENERGY STAR Portfolio Manager also needs to reflect the actual building.
Review items such as:
Gross floor area
Property use types
Operating hours
Number of workers or occupants where applicable
Parking area
Vacancy
Major tenant spaces
Changes in building use
This is particularly important for mixed-use or multi-tenant properties.
A building may contain office space, retail, restaurants, medical uses, or other energy-intensive occupants under the same roof.
Correctly representing those uses provides important context for the building's performance metrics.
What If Tenant Utility Data Is Missing?
Do not simply ignore it.
First determine how much of the property may be missing from the benchmarking record.
Then investigate whether the serving utility can provide aggregated whole-building information or another approved data-access option.
If the building is being benchmarked for a city or state compliance program, review that program's current rules as well. Local requirements can differ regarding utility data, exemptions, estimation, verification, and reporting.
The solution should be based on the specific building and applicable program rather than an assumption that owner-paid data is sufficient.
A Simple Multi-Tenant Benchmarking Checklist
Before submitting a multi-tenant property's benchmarking report, confirm:
Have we identified every utility meter serving the property?
Do we have both owner-paid and tenant-paid energy consumption represented?
Have we investigated aggregated whole-building data where necessary?
Are all common-area and central-system meters included?
Do we have a complete reporting period without unexplained gaps or duplicates?
Are the building's gross floor area and property-use details accurate?
Have tenant turnovers or account changes created missing data?
Does the final dataset represent the entire building?
That last question is the most important.
Whole-Building Data Creates a Better Benchmark
The challenge with multi tenant building energy benchmarking is not simply collecting more utility bills.
It is making sure the data represents what is actually happening across the property.
Owner-paid utilities, tenant meters, aggregated utility data, common areas, central equipment, and building information all contribute to the final picture.
When part of that picture is missing, the resulting benchmark can be misleading.
A useful benchmark should allow an owner to confidently say:
This represents the energy use of our entire building, not just the portion of it that we happen to pay for.
Once that foundation is accurate, metrics such as EUI, ENERGY STAR scores, year-over-year trends, and other performance indicators become much more useful for understanding how the building is actually performing.
