BOMA 2024 Outdoor Areas and CAM: What Changed for Landlords
BOMA 2024 expanded how outdoor and semi-enclosed areas are measured. Here's what changed, how it affects your CAM denominator, and what you need to check in your existing leases before applying new measurements.
Quick Answer
BOMA 2024 expanded the measurement methodology for outdoor and semi-enclosed areas — covered parking structures, exterior corridors, transitional spaces, and amenity areas — potentially changing the total rentable area of your property. This directly affects the denominator used in pro-rata CAM calculations. However, existing leases do not automatically adopt BOMA 2024 measurements unless the lease references the 2024 standard or permits measurement updates.
What BOMA 2024 Changed for Outdoor Areas
Prior BOMA standards (2017, 2012, and earlier) were primarily focused on interior building space. Outdoor and transitional spaces were either excluded from rentable area measurements or handled inconsistently across measurement firms. BOMA 2024 introduced explicit methodology for four categories of outdoor space:
Covered Parking Structures
Multi-level parking structures with a roof or partial enclosure may now be included in rentable area calculations under BOMA 2024, based on the degree of enclosure and intended use. Surface parking lots remain excluded. The inclusion of parking structure area can meaningfully increase the total rentable area of properties with large structured parking — particularly office campuses and mixed-use developments.
Exterior Common Corridors and Covered Walkways
Covered exterior walkways connecting buildings, canopied entries, and exterior corridors between building wings are addressed explicitly in BOMA 2024. These areas, previously categorized inconsistently, now have a defined measurement methodology based on whether they are weather-protected and serve tenant circulation. When included in the rentable area base, they are allocated to tenants as a common area load factor.
Outdoor Amenity Areas
Rooftop terraces, courtyards, and outdoor common amenity spaces that are actively programmed for tenant use may be included in the building's common area under BOMA 2024. This is a significant departure from prior practice, where outdoor amenities were typically excluded from rentable area even if tenants paid maintenance costs for them through CAM.
Transitional Spaces Between Interior and Exterior
Spaces at the boundary of interior and exterior — covered loading areas, semi-enclosed lobbies with operable wall systems, and enclosed atria with exterior-facing features — receive more detailed treatment in BOMA 2024. The standard provides specific criteria for determining whether these spaces are measured as interior rentable area or excluded.
How BOMA 2024 Affects the CAM Denominator
The CAM pro-rata denominator is the total square footage base against which each tenant's share is calculated. If BOMA 2024 remeasurement adds outdoor areas to the total rentable area, the denominator increases — and each tenant's pro-rata percentage decreases (assuming their leased SF is unchanged).
Note: The example above shows a tenant paying less under BOMA 2024 because the larger denominator reduces their percentage. However, if the outdoor areas being added to the denominator also generate CAM expenses (covered parking maintenance, rooftop terrace upkeep), the total recoverable expense pool may also increase — partially or fully offsetting the denominator effect.
Do Existing Leases Automatically Adopt BOMA 2024?
No. Existing leases do not automatically adopt BOMA 2024 measurement standards. The square footage and denominator in a lease are fixed at execution unless the lease specifically includes language permitting measurement updates.
Leases that reference a specific BOMA standard year
If the lease says "measured per BOMA 2017 standards," the 2017 measurement controls for the lease term. A BOMA 2024 remeasurement does not change the lease square footage or denominator without a lease amendment.
Leases that reference "current BOMA standards" dynamically
If the lease says "measured per then-current BOMA standards" or "as updated from time to time," a BOMA 2024 remeasurement may be applicable. Consult counsel before applying updated measurements, as some courts have held that material changes in square footage require tenant consent even under dynamic BOMA references.
New leases executed after BOMA 2024 publication
For new leases, use the phrase "BOMA 2024-aligned where applicable" rather than "BOMA 2024 compliant." Include the measured SF and the denominator as fixed numbers in the lease — do not rely on a dynamic reference to a BOMA standard that may change again in the future.
Practical Steps for Landlords
Get a BOMA 2024-aligned remeasurement
Engage a licensed BOMA-credentialed professional to remeasure your property using the 2024 methodology. Document the difference between the prior measurement and the BOMA 2024 figure, broken down by the specific space categories that changed (covered parking, exterior corridors, amenity areas).
Compare to your prior BOMA measurement
Quantify the delta: how many SF were added or removed by BOMA 2024? Identify the specific space categories driving the change. Model the pro-rata denominator change for each tenant to understand the financial impact before making any billing adjustments.
Review lease language before applying new measurements
For each tenant, review whether the lease references a specific BOMA year, uses a dynamic standard reference, or includes a fixed contractual square footage. Only apply the BOMA 2024 denominator to tenants whose leases explicitly permit it. Do not apply BOMA 2024 measurements unilaterally to leases that reference a prior standard.
For new leases, document the BOMA 2024-aligned figure explicitly
State the measured SF and the denominator as fixed numbers in the lease. Include a notation that the measurement is BOMA 2024-aligned where applicable. Avoid dynamic references to future BOMA updates to provide certainty for both parties.
What Can Go Wrong
Applying new BOMA measurements without checking the lease standard reference
Updating the denominator in your property management system to the BOMA 2024 total without verifying each tenant's lease BOMA reference. If a lease executed in 2019 says "measured per BOMA 2017," billing that tenant using a BOMA 2024 denominator is a lease violation. The tenant can dispute the reconciliation and demand a rerun with the lease-specified measurement.
Remeasuring mid-lease without tenant consent
Even if the lease includes a dynamic BOMA reference, applying a mid-lease remeasurement that materially changes the tenant's leased square footage — and therefore their rent and CAM — without notifying and obtaining consent from the tenant creates legal exposure. The process requires formal notification, the opportunity for the tenant to contest the measurement, and in many cases a right to terminate if the measured SF differs materially from the lease-stated SF.
Inconsistent measurement across multi-tenant floors
In a multi-tenant building, applying BOMA 2024 methodology for some tenants' floor measurements while using prior BOMA for others (based on lease execution date) creates inconsistent load factors. Floor common area loads differ between BOMA versions, which can result in tenants on the same floor having different effective pro-rata contributions that don't reconcile to 100% of the floor.
Frequently Asked Questions
What did BOMA 2024 change about outdoor area measurement?
BOMA 2024 expanded the methodology for measuring covered parking structures, exterior corridors, transitional interior/exterior spaces, and outdoor amenity areas. These areas, previously excluded or measured inconsistently, now have explicit inclusion and allocation methods.
Do existing leases automatically adopt BOMA 2024?
No. Existing leases only adopt BOMA 2024 if they explicitly reference the 2024 standard or include dynamic language permitting measurement updates. Most leases executed before 2024 reference an earlier BOMA standard and are unaffected.
If BOMA 2024 increases rentable area, do tenant pro-rata shares decrease?
Yes — if the denominator increases and the tenant's leased SF is unchanged, their percentage decreases. However, if the additional measured outdoor areas generate CAM expenses, the recoverable expense pool may also increase, partially offsetting the denominator effect.
What does "BOMA 2024-aligned where applicable" mean?
It means the measurement methodology follows BOMA 2024 standards for space types the 2024 standard addresses, while recognizing that some categories may still be governed by prior standards referenced in existing leases. It is more accurate than "BOMA 2024 compliant," which implies formal certification.
Related Resources
Pro-Rata Denominator Explained
How denominator types affect every tenant's CAM share
BOMA 2024 CAM Reconciliation
Full guide to reconciliation impacts of BOMA 2024
BOMA 2024 Standards Overview
Overview of all BOMA 2024 measurement changes
Pro-Rata Calculator
Model pro-rata shares under different denominator definitions
CAM Reconciliation Software
Automate denominator management and pro-rata calculations
Keep Your Denominators Current and Correct
CapVeri tracks the BOMA standard referenced in each lease and flags denominator discrepancies when measurements change — so you don't apply new measurements to leases that don't permit them.
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