CAM Reconciliation for Medical Office Buildings

Medical office buildings sit in a category between standard office and hospital infrastructure. They are not hospitals — they do not have 24/7 operations, surgical suites (usually), or the same regulatory burden. But they are not standard office either. The tenants are physician practices, outpatient clinics, imaging centers, physical therapy facilities, and specialty care providers whose operations require building services that go well beyond what a law firm or accounting firm needs.

This guide covers the expense categories, allocation challenges, and reconciliation errors specific to MOBs.

The MOB CAM Expense Pool

Medical office buildings carry a materially higher cost structure than general-purpose office:

For a 120,000 SF MOB, total recoverable operating expenses typically run $1,464,000 to $2,292,000 annually. The premium over standard office is not incidental — it reflects genuinely different building operations.

After-Hours HVAC: The Defining MOB Expense

In a standard office building, after-hours HVAC is an exception. In a medical office building, it is the norm. Most physician practices open by 7:00 AM (staff arrives at 6:30 for prep) and close at 6:00 or 7:00 PM. Many operate half-days on Saturday. Urgent care tenants may run 8:00 AM to 9:00 PM seven days a week.

If the lease defines standard building hours as 8:00 AM to 6:00 PM Monday through Friday — the typical office definition — then virtually every medical tenant needs after-hours HVAC daily.

Two Approaches to MOB HVAC

Approach 1: Extended standard hours. The MOB lease defines standard hours as 7:00 AM to 7:00 PM Monday through Friday and 8:00 AM to 1:00 PM Saturday. The cost of running HVAC during these extended hours is part of the base CAM pool. All tenants share it pro rata.

This is cleaner for reconciliation because there are fewer after-hours requests to track and bill separately. But it increases the base CAM for every tenant, including any non-medical tenants in the building (an administrative office or a pharmacy) that do not need the extended hours.

Approach 2: Standard office hours with after-hours billing. The lease uses a conventional 8-to-6 definition. Medical tenants request after-hours HVAC and get billed separately.

This is fairer to non-medical tenants but creates an administrative burden. A 15-tenant MOB with 12 medical practices each requesting 2–3 hours of after-hours HVAC daily generates 60+ billing events per week, 3,000+ per year. Tracking and billing accurately at that volume requires either a sophisticated BAS with automated billing integration or dedicated staff time.

The cost difference is real:

A 120,000 SF MOB running HVAC from 7 AM to 7 PM instead of 8 AM to 6 PM adds approximately 4 hours of daily runtime across 260 weekdays = 1,040 additional hours. Add Saturday half-days (5 hours x 52 weeks = 260 hours). Total additional runtime: 1,300 hours.

At $200/hour for a central plant, that is $260,000 in additional annual HVAC cost. Spread across 120,000 SF, that is $2.17/SF added to the CAM pool under Approach 1 — or $260,000 in after-hours charges that need to be allocated to individual tenants under Approach 2.

Medical Waste Disposal

Medical waste disposal is a cost that simply does not exist in standard office buildings. MOB tenants generate regulated medical waste (sharps, biohazard materials, pharmaceutical waste) that requires licensed haulers, specialized containers, and chain-of-custody documentation.

How It Gets Allocated

Direct billing (most common and recommended): Each tenant contracts directly with a medical waste hauler or the landlord arranges service and bills each tenant based on container count and pickup frequency. A primary care practice with 2 sharps containers and biweekly pickup might pay $150–$300/month. An orthopedic surgery center with 8 containers and weekly pickup might pay $800–$1,500/month.

CAM pool (less common, problematic): Some MOBs include medical waste disposal in the common operating expenses. This creates cross-subsidization because a dermatology practice generates far less regulated waste than a blood draw lab. Non-medical tenants in the building (a health insurance office, a medical billing company) generate zero medical waste but pay a pro-rata share.

Enhanced Cleaning Standards

Medical office cleaning goes beyond standard janitorial. Exam rooms require disinfection between patients. Procedure rooms need terminal cleaning. Waiting rooms with high patient traffic need more frequent cleaning than a standard office lobby.

MOB vs. standard office cleaning comparison:

These enhanced standards apply to common areas. Tenant-specific cleaning (inside suites) is the tenant's responsibility and should not be in the CAM pool. But the line blurs in shared corridors where patients with infectious conditions walk, shared restrooms used by patients, and shared waiting areas in multi-practice floors.

The cleaning premium for MOB common areas adds $0.80–$1.50/SF over standard office janitorial. For a 120,000 SF building, that is $96,000 to $180,000 in additional annual janitorial cost attributable to the medical use.

Specialized Fire Suppression

Medical office buildings with oxygen storage, MRI suites, or procedure rooms with anesthesia require fire suppression systems beyond standard wet-pipe sprinklers. These systems include:

• Clean agent suppression (FM-200 or Novec 1230) for MRI rooms where water would destroy $2–5 million imaging equipment
• Pre-action sprinkler systems for areas with sensitive electronics
• Enhanced alarm and monitoring for oxygen-enriched environments
• Automatic gas shutoff valves for medical gas piped systems

The annual maintenance cost for these specialized systems runs $15,000–$40,000 per building, compared to $5,000–$12,000 for standard office sprinkler inspection and maintenance.

Allocation Challenge

Should the cost of the MRI room's clean agent suppression system be in the common CAM pool, or should it be a direct charge to the imaging tenant? The answer depends on the lease and building design:

• If the suppression system is part of the base building infrastructure installed by the landlord, its maintenance is typically a common expense allocated through CAM
• If the tenant installed the system as part of a tenant improvement, its maintenance is typically the tenant's responsibility

The reconciliation error occurs when a tenant-installed system's maintenance gets coded to a common GL account and flows through CAM to all tenants.

ADA Compliance Costs

Medical office buildings face higher ADA compliance standards than standard office because the patient population includes a higher proportion of mobility-impaired individuals. ADA requirements that generate ongoing operating costs include:

These costs are generally recoverable through CAM as part of building code compliance. The reconciliation issue is distinguishing between ongoing ADA maintenance (recoverable) and ADA renovation projects triggered by a tenant improvement (potentially capital, potentially the tenant's responsibility if the TI triggered the path-of-travel requirement).

Under the ADA, if a tenant improvement exceeds a cost threshold, the landlord or tenant may be required to upgrade the path of travel to the improved area. That upgrade cost is tied to the specific TI, not to general building operations, and should not flow through CAM.

Tenant Improvement Allowance Interaction

MOB leases frequently include substantial tenant improvement (TI) allowances because medical buildouts are expensive. A cardiology practice needs plumbing for multiple exam rooms, reinforced flooring for imaging equipment, lead-lined walls for X-ray rooms, and medical gas piping. TI allowances of $60–$120/SF are common for medical buildouts, compared to $30–$60/SF for standard office.

Where TI and CAM Intersect

The TI does not directly affect CAM — it is a capital incentive, not an operating cost. But the improvements funded by the TI can affect operating costs that flow through CAM:

Higher utility consumption. An imaging center with CT and MRI equipment consumes 3–5x more electricity per SF than a standard medical practice. If electricity is in the CAM pool (common area power), and the imaging tenant's equipment drives higher total building electrical costs, the allocation may need adjustment.

Increased HVAC load. Medical equipment generates heat. An imaging suite with a CT scanner requires supplemental cooling. If that cooling is provided by the base building system and charged through CAM, every tenant subsidizes the imaging tenant's cooling load.

Specialized maintenance obligations. Medical gas systems, negative pressure rooms, and enhanced ventilation installed as part of a TI may be maintained by the landlord under the terms of the lease. If that maintenance cost flows through CAM instead of being direct-billed to the tenant whose TI created the system, it is an allocation error.

The rule of thumb: If a building system was installed as part of a specific tenant's improvement and serves only that tenant, its maintenance should be a direct charge, not a CAM expense. If the system serves the building generally (even if one tenant's TI prompted its installation), it belongs in the common pool.

Common MOB Reconciliation Errors

1. Standard Office Hours Used for HVAC Allocation When Extended Hours Apply

The lease says standard hours are 7 AM to 7 PM. The property management system is configured for 8 AM to 6 PM (the default office template). The result: 2 hours of daily HVAC that should be in the base pool are being billed as after-hours charges to individual tenants. The tenants are overcharged for after-hours service they are entitled to receive as part of base CAM.

2. Tenant-Specific Medical Equipment Maintenance in the CAM Pool

A $12,000 annual maintenance contract for the radiology tenant's lead-lined door is coded to "door hardware maintenance" in the building's GL. It flows through CAM to all tenants. That contract should be a direct charge to the radiology tenant.

3. Pharmaceutical Waste Costs Allocated Pro Rata

The building contracts with a pharmaceutical waste disposal company for $36,000/year. That cost is allocated pro rata across all 15 tenants at $2,400 each. But 3 tenants are non-medical (health insurance, medical billing, medical legal). They generate zero pharmaceutical waste. And among the medical tenants, a compounding pharmacy generates 10x the pharmaceutical waste of a psychiatry practice.

4. Hospital-System Mandated Costs Passed Through

When the MOB is affiliated with a hospital system, the system sometimes imposes standards (branding, IT infrastructure, security protocols) that exceed market norms. The cost of meeting hospital-system mandates may not be recoverable through CAM unless the lease specifically permits it. A $50,000 annual charge for the hospital system's mandated security platform is not a standard operating expense.

5. Water Costs Not Sub-Metered

Medical tenants use significantly more water than standard office tenants (exam room sinks, sterilization, lab work). A pro-rata water allocation by SF unfairly charges a psychiatry practice (which uses standard office water volumes) the same rate as an outpatient surgery center. Sub-metering is the solution, but many MOBs were built without tenant-level water meters.

How CapVeri Handles MOB CAM

Medical office reconciliation requires sensitivity to the cost premium and the allocation granularity that MOB tenants expect. CapVeri addresses this with:

• Extended hours configuration: Supports custom standard-hour definitions per building so HVAC allocation matches lease terms, not default office templates
• Direct charge separation: Flags medical-specific GL accounts (waste disposal, specialized maintenance) for review to ensure tenant-direct costs are not in the common pool
• Utility variance detection: Identifies tenants whose utility consumption deviates significantly from the building average, flagging potential sub-metering or allocation issues
• TI-related cost tracking: Tags maintenance contracts associated with tenant-specific improvements so they can be excluded from the common pool

The result is a reconciliation that reflects the actual cost structure of medical office operations, not a standard office template with medical costs layered on top.

Related Resources

• CAM Reconciliation for Office Buildings — Standard office CAM as a baseline comparison
• After-Hours HVAC and CAM Allocation — What belongs in the base pool vs. direct billing
• CAM Gross-Up Calculation Guide — Vacancy adjustments that affect MOB cost allocation
• Self-Audit CAM Billing — Catching errors before tenants do