"Common area maintenance" implies a simple idea: tenants share the cost of spaces everyone uses. Lobbies, parking lots, elevators, restrooms, spaces that benefit every tenant in the building. Sharing that cost makes sense.
What does not make sense is a tenant paying to maintain a space that benefits only one other tenant, or a space that serves the landlord's own operations and nothing else. That is what happens when a landlord misclassifies a dedicated space as common area.
I built CAMAudit because these misclassifications are common, and they are hard to catch without reading the underlying service records. A CAM statement does not label a line "HVAC serving only Suite 200." It just says "HVAC maintenance." Whether that expense is truly shared sits in the vendor's service records, not the statement.
What Makes a Space "Common Area"
The definition of common area is not universal. It varies by lease. Most leases define it as something like: areas available for use by all tenants and their employees, customers, and invitees, including lobbies, corridors, restrooms, elevators, parking areas, and similar shared facilities.
The operative word is "available." A space open to all tenants fits. A space dedicated to one tenant's exclusive use does not. A space that exists only to serve the landlord's management office does not either.
That sounds simple. In practice the boundary gets blurry, sometimes on purpose.
Classic Misclassification Patterns
HVAC Serving Only One Tenant's Space
This is the most common type CAMAudit flags. A large-format tenant, a grocery store, a fitness center, a movie theater, often runs its own HVAC units because its heating and cooling load looks nothing like a standard office or shop.
Those units serve only that tenant. But the maintenance cost for them sometimes lands in the building-wide HVAC maintenance line, which gets split across all tenants by pro-rata share.
The result: a small tenant pays a slice of the maintenance cost for equipment that exclusively cools a 30,000-square-foot grocery anchor. The anchor's own lease may even carve its HVAC out as a direct cost, so it pays nothing through CAM for equipment it alone uses, while its neighbors absorb part of the bill through a misclassified line.
Check the "HVAC maintenance" line. Ask the landlord: what equipment is in this figure? Which units? Which floors or zones do they serve?
Parking Reserved for Landlord or Anchor Staff
Many properties include surface parking or a structured garage. The lease defines which parking areas count as common area, available to everyone. Sometimes a section of that lot, executive spaces near the entrance, or a full level of the garage, is effectively reserved for the landlord's staff or one anchor tenant.
The maintenance cost for that reserved parking still gets spread across all tenants through the general parking line. Tenants who cannot even use those spaces are paying to stripe and light them.
This one takes a site visit, or a parking layout diagram from the landlord. If certain spaces are reserved or consistently unavailable to the general tenant population, they should not be in the common area denominator.
Roof Equipment Serving a Single Floor or Tenant
Rooftop equipment for telecom, supplemental cooling, or specialty electrical sometimes serves only one tenant. Maintenance and replacement for that equipment is usually that tenant's obligation alone under most leases.
When a landlord groups all rooftop maintenance into one line, "Roof and mechanical maintenance," and allocates it proportionally, every tenant absorbs a share of costs that have nothing to do with them.
The Landlord's Own Office Space
Property management companies often occupy space in the building they manage. That space serves the landlord's own operations. Its HVAC, lighting, cleaning, and maintenance costs are landlord overhead, not common area expenses.
Some landlords try to pass those costs through CAM anyway. This overlaps with Rule 13 (Landlord Overhead Pass-Through), but it also shows up as common area misclassification when management-office costs get bundled into an engineering or facilities line instead of appearing as a separate management fee.
Why This Matters for the Client
The principle behind CAM cost-sharing is that each tenant pays for a benefit it actually receives. Misclassify a space or system as common area, and that principle breaks. The client is paying for maintenance of something it does not use, cannot access, or that exists solely for someone else's benefit.
A few hundred dollars a year might read as noise. But misclassification compounds annually. If an HVAC unit serving only a large anchor adds $15,000 a year to the common area pool, and the client's pro-rata share is 8%, that is $1,200 a year for equipment they have no connection to. Over a ten-year lease, that is $12,000.
The larger the building and the more anchor tenants it has, the more room there is for this error.
How to Spot Misclassification in a Statement
Check these lines first:
Building engineering / engineering labor. Do these engineers service systems that exclusively serve other tenants?
HVAC maintenance. What equipment, what zones, which tenants benefit?
Parking area maintenance. Is any parking reserved or effectively off-limits to the client?
Janitorial services. Is cleaning done in spaces the client cannot access, the landlord's management office, for example?
Roof maintenance and repairs. What equipment is on the roof, and who does it serve?
Then run the lease test: find the definition of "common area" or "common areas and facilities" in the lease. Read it closely. Check each CAM line item against that definition.
If the answer is "we cannot tell," that is itself a finding. The landlord should be able to produce documentation supporting each line item under the audit rights clause.
"Common area misclassification is subtle because the expense category sounds legitimate. HVAC maintenance is a real common area expense, unless the specific units being maintained serve only one tenant. That distinction takes documentation, and most reviews never ask for it." - Angel Campa, Founder of CAMAudit
The Lease Language Test
When reviewing a client's lease for protection against misclassification, look for:
Specific exclusions from common area costs. Some leases state that costs attributable exclusively to one tenant's space are excluded from common area expenses. This is the strongest protection.
HVAC exclusions. If the lease says each tenant is responsible for HVAC serving its own premises, dedicated tenant HVAC cannot enter the CAM pool.
Anchor carve-outs. In a multi-tenant retail center, check whether the lease addresses how anchor tenant obligations interact with common area costs. If an anchor negotiated out of certain CAM categories, are those costs being redistributed to other tenants?
Common area tied to all-tenant availability. The tighter the definition, specifically requiring availability to all tenants, the harder it is to slip in a dedicated space.
CAMAudit Rule 12: Common Area Misclassification
When your firm routes a client's lease and CAM statement through CAMAudit, Rule 12 uses that lease's common area definition as the baseline. It flags line items where the expense description, vendor, or category points to a cost typically associated with dedicated rather than shared space.
It also checks the statement against the lease's explicit exclusions. If the lease excludes a category and that category still shows up on the statement, Rule 12 surfaces it for your team's review.
The rule cannot independently confirm which physical space a vendor actually serviced. That takes the landlord's backup documentation. But it identifies the lines worth a documentation request, which is where most reviews stop short.
Knowing which lines to challenge is half the work. Once the specific line items are flagged, requesting the underlying service records becomes a targeted ask instead of a fishing expedition.
What to Do When Your Firm Finds a Misclassification
Start with a documentation request. Under the client's audit rights, ask the landlord for:
- Vendor invoices for the flagged line items
- Service records showing which areas, floors, or equipment were serviced
- Building plans or equipment schedules showing where the serviced systems sit
With that documentation, match the expense to the lease's definition. If the serviced space or system does not fit, it is a billing error.
The dispute letter draft CAMAudit builds cites the specific lease language, the line item, and the documentation gap. That gives your team a concrete starting point for the conversation with the landlord instead of a vague complaint. It is a draft for review, not legal advice; have counsel review it before it goes out.
Common area misclassification rarely shows up as an obvious error. The line items look plausible. The amounts are real. The mistake is in the classification, and classification errors only surface when your team matches each line against the lease's specific definition and asks for documentation to back it up.
Most reviews never ask. That is exactly why these errors persist.