The phrase "common area maintenance" implies a simple idea: tenants share the cost of maintaining spaces that everyone uses. Lobbies, parking lots, elevators, restrooms — spaces that benefit all tenants in the building. The cost-sharing makes sense.
What does not make sense is paying to maintain a space that only benefits one tenant, or worse, a space that benefits the landlord's own operations and nothing else. But that is exactly what happens when a landlord misclassifies dedicated spaces as common area.
I built CAMAudit because these misclassifications are surprisingly common, and they are hard to catch without reading the underlying documentation carefully. The cam statement does not label a line "HVAC serving only Suite 200." It just says "HVAC maintenance." Whether that expense is truly shared is buried in the 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 of the building 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 that is available to all tenants qualifies. A space that is dedicated to a single tenant's exclusive use does not. A space that exists solely to serve the landlord's management office does not.
This sounds simple. In practice, the boundary gets blurry — intentionally or not.
40% of CAM reconciliations contain material errors, with misclassified expenses among the most frequently disputed categories (Tango Analytics / PredictAP, 2023)
Classic Misclassification Examples
HVAC Serving Only One Tenant's Space
This is the most common type CAMAudit flags. A large-format retail tenant — a grocery store, a fitness center, a movie theater — often has its own HVAC units because their heating and cooling loads are dramatically different from a standard office or shop.
Those units serve only that tenant. But the maintenance costs for those units sometimes end up in the building-wide HVAC maintenance line, which gets split across all tenants by pro-rata share.
The result: a small boutique tenant pays a fraction of the maintenance cost for equipment that exclusively cools a 30,000-square-foot grocery anchor. The anchor tenant may even have a lease that specifically carves out its HVAC as a direct operating cost — meaning it pays nothing through CAM for equipment it exclusively uses, while its neighbors absorb part of the bill through misclassified common area charges.
Look at your "HVAC maintenance" line. Ask your landlord: what equipment is included in this figure? Which units? Which floors or zones do they serve?
Parking Reserved for Landlord or Anchor Employees
Many commercial properties include surface parking or structured garages. The lease defines which parking areas are common areas available to all tenants. But sometimes a section of that parking — executive spaces near the building entrance, or an entire level of the garage — is effectively reserved for the landlord's management staff or a specific anchor tenant.
The maintenance cost for that dedicated parking area still gets allocated across all tenants through the general parking/common area line. Tenants who cannot even use those spaces are paying to stripe and light them.
This one requires looking at the actual site — or requesting 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 telecommunications, supplemental cooling, or specialty electrical systems sometimes serves only one tenant. Maintenance, repair, and replacement costs for that equipment are the exclusive obligation of that tenant under most leases.
When landlords group all rooftop equipment maintenance into a single line — "Roof and mechanical maintenance" — and allocate 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 within the building they manage. That space is dedicated to the landlord's operations. Its HVAC, lighting, cleaning, and maintenance costs are not common area expenses — they are the landlord's overhead.
Some landlords attempt to pass the operational costs of their management offices through CAM. This overlaps with Rule 13 (Landlord Overhead Pass-Through) but also surfaces as a common area misclassification when the management office costs get bundled into building engineering or facilities maintenance lines rather than appearing as a separate management fee.
Why This Matters: You're Paying for Something That Doesn't Benefit You
The principle underlying CAM cost-sharing is that each tenant pays for benefits they receive. When a space or system is misclassified as common area, that principle breaks down. You are paying for maintenance of something you do not use, cannot access, or that exists solely for someone else's benefit.
On a small scale — a few hundred dollars — it might feel like noise. But misclassification errors compound annually. If an HVAC unit serving only a large anchor tenant adds $15,000 per year to the common area pool, and your pro-rata share is 8%, you are paying $1,200 per year for equipment you 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 potential there is for this type of error.
How to Spot Misclassification in Your Statement
The most productive lines to examine are:
Building engineering / engineering labor. Ask specifically: are these engineers servicing systems that exclusively serve other tenants?
HVAC maintenance. As described above — what equipment, what zones, which tenants benefit?
Parking area maintenance. Is any parking area reserved or effectively inaccessible to you?
Janitorial services. Is cleaning performed in areas you cannot access? Landlord management offices, for example?
Roof maintenance and repairs. What equipment is on the roof, and who does it serve?
The lease language test is straightforward: find the definition of "common area" or "common areas and facilities" in your lease. Read it carefully. Then look at each CAM line item and ask whether the maintained space or system fits that definition.
If the answer is "I cannot tell," that is itself a problem. Your landlord should be able to provide documentation supporting each line item under your audit rights.
"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 requires documentation, and most tenants never ask for it." — Angel Campa, Founder of CAMAudit
The Lease Language Test
When reviewing your lease for protection against common area misclassification, look for:
Specific exclusions from common area costs. Some leases explicitly state that costs attributable exclusively to a single tenant's space shall not be included in common area expenses. This is the strongest protection.
HVAC exclusions. If your lease says each tenant is responsible for the HVAC serving their own premises, that should mean dedicated tenant HVAC cannot enter the CAM pool.
Anchor tenant carve-outs. In a multi-tenant retail center, check whether your lease addresses how anchor tenant obligations interact with common area costs. If an anchor tenant has negotiated out of certain CAM categories, are those costs being redistributed to other tenants?
Common area definition tied to all-tenant availability. The stronger the definition — specifically requiring availability to all tenants — the harder it is to include dedicated spaces.
CAMAudit Rule 12: Common Area Misclassification
When you upload your lease and CAM statement, CAMAudit's Rule 12 uses your lease's common area definition as the baseline. It flags line items where the expense description, vendor, or category suggests costs that are typically associated with dedicated rather than shared spaces.
It also cross-references against your lease's explicit exclusions. If your lease says certain categories are excluded from common area expenses, and those same categories appear in the statement, Rule 12 surfaces them for review.
The rule cannot independently verify which physical spaces a vendor actually serviced — that requires your landlord's backup documentation. But it can identify the lines that warrant documentation requests, which is where most tenants stop short.
Knowing which lines to challenge is half the work. Once you have the specific line items flagged, requesting the underlying service records becomes a targeted exercise rather than a fishing expedition.
What to Do When You Find a Misclassification
Start with a documentation request. Under your audit rights, ask your landlord for:
- Vendor invoices for the flagged line items
- Service records specifying which areas, floors, or equipment were serviced
- Any building plans or equipment schedules showing where the serviced systems are located
With that documentation, you can match the expense to the definition in your lease. If the serviced space or system does not fit the common area definition, you have a billing error.
The dispute letter draft CAMAudit generates references the specific lease language, the line item in question, and the documentation gap. That gives you a concrete starting point for the conversation with your landlord rather than a vague complaint.
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 you match each line against the specific definition in your lease and ask for documentation to support it.
Most tenants never ask. That is precisely why these errors persist.