BOMA 2024 Changes: What the Updated Standards Mean for Your CAM Bill
BOMA 2024 refers to the Building Owners and Managers Association's updated measurement standards for office buildings, released in 2024. The revision modifies how certain building areas are classified, measured, and allocated between leasable and non-leasable categories. For commercial tenants, these changes affect the denominator used to calculate pro-rata share, which directly affects how much each tenant pays for CAM charges.
Most tenants do not know which BOMA standard their lease references, let alone what changed in 2024. This guide explains the relevant changes, how they affect CAM billing, and what lease language protects you from unexpected share increases due to remeasurement.
Key Takeaways
- BOMA 2024 modifies how certain shared spaces (building amenities, service areas, and multi-tenant corridors) are classified, which can change both tenant and building RSF.
- If your lease specifies a particular BOMA standard, the landlord cannot unilaterally remeasure under a different standard without a lease amendment.
- Remeasurement under BOMA 2024 may increase or decrease your pro-rata share depending on the building's configuration.
- BOMA standards apply primarily to office leases. Retail leases typically use ICSC/GLA definitions that follow a different methodology.
- The practical protection for tenants is explicit lease language locking the denominator to a specific BOMA standard and year.
What BOMA Standards Are and Why They Matter
The Building Owners and Managers Association publishes measurement standards that define how rentable area is calculated for office and other commercial building types. (Source) The standards are not law; they are voluntary industry conventions. Their importance is that most commercial leases adopt BOMA standards by reference.
A lease that says "rentable area as determined by BOMA standards" leaves open which version applies. A lease that says "rentable area as determined by the 2017 BOMA standard for office buildings" is explicit.
Different BOMA versions use different formulas for the "load factor" or "R/U ratio" : the multiplier that converts usable area (the physical space within a tenant's walls) to rentable area (the space including an allocated share of building common areas). A higher load factor produces a higher RSF for the same usable area.
The load factor impact on rent and CAM:
If your usable area is 4,000 SF and the load factor is 1.15, your rentable area is 4,600 SF. Under a different BOMA standard with a 1.12 load factor, your rentable area would be 4,480 SF. The difference (120 SF) affects both your base rent and your pro-rata share calculation.
For pro-rata share: if your RSF changes from 4,600 to 4,480 while the building denominator stays constant, your share decreases. If your RSF stays constant but the building denominator changes due to reclassification of common areas, your share may increase or decrease depending on the direction.
What Changed in BOMA 2024
BOMA 2024 is a revision to the 2017 standard. The key changes relevant to tenants:
| Area | BOMA 2017 Treatment | BOMA 2024 Treatment | Impact |
|---|---|---|---|
| Building amenity spaces | Allocated as building common area | May be classified differently depending on shared-use criteria | Can change building denominator |
| Service areas (mechanical rooms, etc.) | Included in floor common area allocation | Revised allocation methodology | Can affect load factor |
| Exterior covered areas | Variable treatment | Clarified classification rules | May affect tenant RSF |
| Multi-tenant floor corridors | Floor-level common area | Updated allocation approach | Can change per-floor load factor |
The practical effect of these changes depends on the specific building configuration. Not every building will be affected equally, and some buildings will see minimal changes when remeasured under BOMA 2024.
BOMA 2024 vs. BOMA 2017: The Specific Changes
| What Changed | BOMA 2017 | BOMA 2024 | Impact on Your CAM |
|---|---|---|---|
| Ground-level outdoor amenities | Excluded from rentable SF | Patios, terraces, and courtyards now included | Expands denominator; dilutes your share slightly if your space did not change |
| Balconies and rooftop terraces | Load factor penalty applied | Classified as Non-Allocated Tenant Area; measured at 100%, no load factor | Eliminates RSF discount on premium amenity space |
| Base building circulation (Method B) | Complex multi-step allocation | Simplified proportional floor allocation | Reduces disputes; small RSF increase per floor |
| Tenant storage areas | Multiple classification categories | Single streamlined category | Cleaner pro-rata allocation; fewer CAM exclusions |
| Single-tenant equipment shafts | Excluded or ambiguous | Explicitly billable RSF | Incremental addition to total building SF |
Net effect across a typical commercial portfolio: a 2–5% increase in total rentable SF per building when adopting BOMA 2024 from BOMA 2017.
To see the math: a 150,000 RSF office building where a tenant occupies 10,000 RSF starts at a 6.67% share. Under BOMA 2024, the building remeasures to 157,500 RSF (a 5% increase). If the tenant's space stays at 10,000 RSF, the share drops to 6.35%. On a $500,000 annual CAM pool, that's the difference between $33,333 and $31,746, a $1,587 annual reduction. If the landlord adopted the new building total but did not adjust the tenant's share, the tenant may be overpaying by that amount each year.
The Non-Allocated Tenant Area problem
The most impactful single change in BOMA 2024 is the reclassification of balconies and rooftop terraces as "Non-Allocated Tenant Areas" (NATA). Under BOMA 2017, these spaces carried a load factor the same as interior tenant areas. Under BOMA 2024, they are measured at 100% of their actual area with no load factor applied.
In a mixed-vintage lease book, where some leases were signed under BOMA 2017 measurements and others under BOMA 2024, the two standards produce different denominators. If you are a tenant in a building with balconies or rooftop terraces and your landlord adopted BOMA 2024, verify whether your own space was remeasured and whether the pro-rata share in your reconciliation reflects a consistent measurement methodology.
How Remeasurement Can Affect Your Pro-Rata Share
Landlords remeasure buildings when: they are seeking BOMA certification, they are refinancing and need updated square footage figures, they are executing new leases and want current measurement documentation, or they are disputing a tenant's measurement claim.
Scenario A: Your RSF increases, building total stays constant. Your numerator increases, your share increases, your annual CAM bill increases.
Scenario B: Your RSF stays constant, building total changes. If the denominator increases, your share decreases. If the denominator decreases (due to reclassification of some area as non-leasable), your share increases.
Scenario C: Both change in the same direction. The net effect depends on which changes more proportionally.
Scenario D: The BOMA standard changed but your lease is explicit. If your lease specifies "BOMA 2017 standard" and the landlord remeasures under BOMA 2024, the remeasurement does not affect your lease obligations. The landlord may use the new measurement for new leases but cannot impose it on existing leases without your consent.
Lease Language: What Protects You and What Doesn't
Strong protection: Lease language that explicitly locks the measurement standard and the denominator RSF:
"Tenant's pro-rata share shall be calculated using (a) the rentable square footage of the Premises as set forth in Section 1 of this Lease, and (b) the total rentable area of the Building as of the Commencement Date, as measured under the BOMA 2017 standard for office buildings, being [specific RSF]."
This language sets both your numerator and the denominator at fixed values. Neither can change without a lease amendment.
Weak protection: Language that references "BOMA standards" without specifying a year or that reserves the landlord's right to remeasure:
"Tenant's pro-rata share shall be based on the rentable area of the Premises relative to the total rentable area of the Building, as such areas may be measured or remeasured from time to time."
"From time to time" gives the landlord unilateral remeasurement rights, which can increase your share after a new measurement standard is adopted.
No protection: Leases that are silent on measurement standard. These leave the applicable standard open to interpretation, creating ambiguity that landlords typically resolve in their own favor.
Specific BOMA 2024 Changes and Their Tenant Impact
BOMA 2024 introduced several classification and allocation changes from the 2017 standard. While the full technical specification requires access to the BOMA publication, the changes relevant to tenants fall into three practical categories:
Change 1: Building amenity area classification
BOMA 2024 revised how amenity spaces shared by all building tenants are classified and allocated. Spaces like fitness centers, conference rooms, and common lobbies may be classified differently depending on whether their use is shared among all tenants, available only to certain floors, or functionally tied to specific tenant suites.
Under BOMA 2017, many amenity spaces were allocated as building-wide common area, adding load factor to all tenants equally. Under BOMA 2024, the classification is more specific, which can shift how load factor is distributed. Some tenants on floors near amenity spaces may see higher load factors; those on other floors may see lower ones.
Tenant impact: If building amenities changed classification, your RSF may have changed even though your physical space is identical. Request the pre- and post-remeasurement RSF figures and the specific classification that changed.
Change 2: Service and mechanical area allocation methodology
BOMA 2024 updated the methodology for allocating service areas : mechanical rooms, elevator shafts, stairwells, and janitorial closets : across floor-level common area calculations. The change affects the "floor common area factor," which is one component of the total load factor.
Buildings with large mechanical footprints may see different load factor distributions after BOMA 2024 remeasurement than under BOMA 2017. In most office buildings, this change produces modest RSF adjustments (typically less than 1% to 3% of tenant RSF), but on a 5,000 SF tenant in a large building with significant mechanical infrastructure, even a 2% adjustment can change annual CAM by thousands of dollars.
Change 3: Exterior covered area treatment
BOMA 2024 clarified the treatment of covered exterior areas: covered parking, exterior corridors, loading docks, and similar spaces. Under BOMA 2017, the treatment varied by property; under BOMA 2024, the classification rules are more explicit.
For tenants in buildings where exterior covered areas were previously unclassified or classified inconsistently, BOMA 2024 remeasurement may reclassify those areas in ways that affect the total building RSF and, consequently, each tenant's pro-rata share.
How to Audit a Post-BOMA 2024 Remeasurement
If your landlord has remeasured the building under BOMA 2024 and your pro-rata share has changed, this is an auditable event. The audit process for a remeasurement dispute differs from a standard CAM overcharge review:
Document request 1: The remeasurement report. Request the full BOMA certification or measurement report. This document should show the methodology, the classification decisions made for each space type, and the resulting RSF figures for both tenant and building.
Document request 2: The prior measurement basis. Request the prior RSF documentation: the measurement basis used before BOMA 2024 was applied. Without this, you cannot calculate the change or verify whether the new figures are correct.
Document request 3: The lease definition. Your lease's pro-rata share and RSF definitions govern whether the new measurements apply. If the lease specifies BOMA 2017 or locks in a specific RSF number, those provisions override the remeasurement.
Verification step: If both the tenant RSF and the building total RSF changed, calculate each percentage and compare. A building that went from 120,000 to 125,000 SF while your space went from 5,000 to 5,100 SF does not produce the same share change as a building that stayed at 120,000 SF while your space went to 5,100 SF. The net effect of both numbers changing simultaneously requires careful math.
BOMA and Retail Properties: A Different Standard
BOMA 2024 applies primarily to office buildings. Retail properties use the International Council of Shopping Centers (ICSC) gross leasable area (GLA) definition, which operates differently:
- GLA measures the total floor area designed for tenant use and exclusive occupancy
- GLA typically excludes anchor tenant areas from the denominator in some shopping center contexts
- Retail leases specify GLA rather than BOMA RSF as the allocation basis
Retail tenants should verify which standard their lease uses. A retail lease that references BOMA instead of ICSC/GLA may produce a different share calculation than intended, particularly in mixed-use properties where parts of the building are office-classified.
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Scan My Lease NowWhat to Do If Your Landlord Remeasures
If you receive a notice that the building has been remeasured and your pro-rata share is changing:
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Review your lease immediately. Check whether the lease specifies a measurement standard, locks the denominator RSF, or contains remeasurement rights language.
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Request the remeasurement documentation. Ask for the BOMA certification or measurement report, the methodology used, and the specific changes to your tenant RSF and the building total RSF.
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Compare before and after. Calculate your pre-remeasurement share and your post-remeasurement share. Determine the annual dollar impact.
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Evaluate your dispute rights. If the lease specifies a particular BOMA standard and the landlord remeasured under a different one, you have grounds to dispute the new allocation. If the lease is silent, the dispute is more difficult but still worth evaluating.
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Consult a tenant representative. Remeasurement disputes are fact-intensive and often require a property-specific analysis. A tenant representative broker or commercial real estate attorney can evaluate whether the remeasurement complies with your specific lease.
Frequently Asked Questions
Related Resources
Pro-rata share and measurement:
- Pro-rata share calculator : Verify your percentage with correct denominator
- Common area maintenance reconciliation tenant guide
- NNN lease audit guide
Lease language:
Tools:
- Pro Rata Share Calculator : Verify your denominator
- CAM Overcharge Estimator
- Start Your Free Scan
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