A CAM cap is a lease provision that limits how much a tenant's share of common area maintenance charges can increase from one year to the next, usually expressed as a percentage such as 5%. Caps almost always apply only to controllable expenses, the costs a landlord can influence through management decisions, and never to taxes, insurance or utilities. Whether the cap is cumulative, non-cumulative or compounding changes what a tenant pays by six figures over a ten-year lease, on identical wording everywhere else.

That last sentence is the point of this post. The rate on a cap gets negotiated hard. The type of cap gets skimmed, and it's worth more.

Why caps exist, and what they are not

Tenants sign triple-net or modified-gross leases knowing operating costs will pass through to them. What they can't know is how well the building will be run. A cap gives the tenant a ceiling on the costs the landlord controls, so a management company that lets the janitorial contract drift 12% a year can't pass all of it through.

A cap is not a fixed expense stop and it is not a budget. It's a ceiling on growth, applied each year to a defined subset of expenses. Three decisions define it: which expenses it covers, how the ceiling is calculated, and whether unused headroom carries forward.

Controllable vs non-controllable expenses

The cap applies to controllable expenses. Everything else passes through at actual, uncapped. The lease should list both categories; where it only lists non-controllables, everything not on that list is controllable by default.

The logic behind the uncapped column is that the landlord has no lever to pull. A county can raise taxes 18%; a hurricane can double the insurance premium; a new fire code can require a $40,000 system upgrade. Tenants accept those. What they push back on is a "non-controllable" list that quietly grows each renewal to include management fees, security and anything with a contract attached.

Snow removal deserves a note. It's usually non-controllable because the weather is, but a tenant in Minneapolis will sometimes negotiate a five-year rolling average so that one bad winter doesn't produce a spike. Utilities for common areas are non-controllable in almost every lease, though a tenant can ask for a cap on the rate the landlord agrees with the supplier.

The three cap types, and why the difference is six figures

The cap percentage is the same in all three examples below: 5%. The base is the same: a 50,000 sf tenant whose year-one controllable expenses are $300,000 ($6.00/sf). The actual controllable expenses grow unevenly, as they always do, because a contract renegotiation lands in one year and a quiet year follows.

1. Non-cumulative cap: Each year's charge cannot exceed the prior year's actual controllable expenses plus 5%. Unused headroom disappears. If expenses grow 1% one year, the tenant gets no credit for the 4% the landlord didn't use.

2. Cumulative cap (non-compounding): The charge in any year cannot exceed the base-year figure plus 5% for each year elapsed: 5% in year two, 10% in year three, 15% in year four. Unused headroom carries forward, but the increments are calculated on the base, so they don't compound.

3. Cumulative compounding cap: The charge cannot exceed the base-year figure grown at 5% per year compounded: 5% in year two, 10.25% in year three, 15.76% in year four. Unused headroom carries forward and the ceiling compounds.

Here is what each does over five years:

Over five years the three caps land within $7,000 of each other. That's why negotiators skim past the type. Now extend the same lease to ten years, with expenses growing a steady 6% a year after year five:

Same 5%. Same tenant. The cumulative non-compounding cap is worth $156,588 more to the tenant over ten years than the non-cumulative one, and the landlord who agreed to it without noticing the word "cumulative" has given away that amount.

The mechanism: a non-cumulative cap re-bases every year on actual expenses, so it only bites in years when growth exceeds 5%, and it never claws back the quiet years. A cumulative cap keeps its ceiling anchored to year one, so every year of growth above 5% is permanently squeezed against a line that only rises 5% a year. Compounding sits between the two, because the ceiling grows faster than a straight 5%-of-base increment.

Which one you want depends on which side of the table you're on. Landlords want non-cumulative on the prior year's actual. Tenants want cumulative non-compounding on the base year. Most negotiated leases end up at cumulative compounding, and most of the ones that don't got there by accident.

The standard CAM exclusions list

Exclusions are different from caps. A cap limits growth in a category; an exclusion removes an item from the pool altogether, before any cap or gross-up is applied. Every tenant-side lawyer carries a list. This is the one that survives most negotiations:

Capital and ownership costs

• Capital improvements and replacements, other than those that reduce operating costs (amortised over useful life, with the amortised amount capped at the saving)
• Costs of constructing, expanding or reconfiguring the building or any tenant's premises
• Depreciation and amortisation, except as above
• Debt service, ground rent, mortgage interest and financing costs
• Costs of acquiring or selling the property

Leasing costs

• Leasing commissions, advertising, marketing and promotional costs
• Tenant improvements, allowances, inducements and concessions for any tenant
• Legal fees for lease negotiation, enforcement or disputes with other tenants
• Costs of vacant space, including utilities and improvements to it

Landlord overhead and profit

• Landlord's general corporate overhead and salaries above the level of building manager
• Management fees above a stated percentage (typically 3–5% of gross receipts)
• Fines, penalties and interest arising from the landlord's late payment or non-compliance
• Costs reimbursed by insurance, warranties or other tenants

Compliance and environmental

• Costs of remediating hazardous materials present before the lease commencement
• Costs of correcting building-code violations that existed at commencement
• ADA or accessibility work required at commencement

Services not shared

• Services provided to one tenant but not to others, or to a materially greater degree
• Costs arising from the landlord's negligence, breach or wilful misconduct
• Charitable or political contributions, art, entertainment and gifts

Two items in that list carry the most money. The capital exclusion is the biggest by value; a roof replacement charged through CAM as "repairs" is a five- or six-figure argument. The management-fee cap is the one most often missing; without it, a landlord can charge a 6% fee on a building where the market is 3%, and the difference lands in the pool.

How caps interact with gross-ups and exclusions

Order of operations matters, and most disputes about caps are really disputes about sequence.

1. Exclusions first - Remove excluded items from the expense pool.
2. Gross-up second - Adjust variable expenses to the target occupancy. Our CAM gross-up worked example shows the calculation.
3. Cap third - Test the grossed-up controllable total against the cap.
4. Allocate last - Apply the tenant's pro-rata share.

Run the cap before the gross-up and the ceiling is tested against a smaller number than the one you then bill, which overcharges the tenant. Run allocation before exclusions and the tenant is paying a share of items the lease says they never owed. Neither error is subtle in an audit.

Caps also have to be tested against the grossed-up base year. If the base year is $300,000 at 90% occupancy but the lease grosses up to 95%, the cap's anchor is the grossed-up base, not the raw one. Anchor to the wrong number and the cap is wrong in every year of the lease.

Tracking caps per lease in NetSuite

A cap is a per-lease rule with four attributes: the percentage, the type (non-cumulative, cumulative, compounding), the base-year amount it anchors to, and the list of expense accounts it applies to. Once those live on the lease record, the annual reconciliation can test each tenant's controllable share against its own ceiling automatically and show the tenant the cap calculation on the statement.

In a property management system that runs inside NetSuite, expense accounts are tagged controllable or non-controllable per building, the exclusion list is enforced at the account level so excluded costs never reach the pool, and each lease carries its cap type and base. When the reconciliation runs, the system applies exclusions, gross-up, cap and allocation in that order and stores the workings. That's how RIOO handles CAM on NetSuite. The test for any system: create two identical leases, set one cap to cumulative and the other to non-cumulative, run five years of expenses through both, and confirm the totals differ. If they match, the system is ignoring the cap type.

Frequently asked questions

Q1. What is a CAM cap?
A CAM cap limits how much a tenant's share of common area maintenance charges can rise year over year, usually by a stated percentage such as 5%. It normally applies only to controllable expenses, with taxes, insurance and utilities passed through uncapped.

Q2. What are controllable expenses in a commercial lease?
Controllable expenses are operating costs the landlord can influence through management decisions: janitorial, landscaping, routine repairs, supplies, administrative fees and similar contracts. Non-controllable expenses, such as property taxes, insurance, utilities, snow removal and costs imposed by new laws, are outside the landlord's control and are excluded from the cap.

Q3. What is the difference between a cumulative and non-cumulative CAM cap?
A non-cumulative cap limits each year's increase to a percentage over the prior year's actual expenses, and unused headroom is lost. A cumulative cap limits the charge to the base-year amount plus the percentage for each year elapsed, so unused headroom carries forward. Over a long lease the cumulative version is significantly more favourable to the tenant.

Q4. What is a compounding cap?
A compounding cap grows the ceiling by the cap percentage each year on the previous year's ceiling, rather than on the base year. At 5%, the ceiling in year four is 15.76% above base under a compounding cap and 15% above base under a non-compounding cumulative cap.

Q5. What expenses are typically excluded from CAM?
Capital improvements, debt service, depreciation, leasing commissions, tenant improvements, landlord corporate overhead, management fees above an agreed percentage, costs reimbursed by insurance or other tenants, pre-existing environmental and code compliance costs, and services provided to one tenant only.

Related reading

• CAM gross-up example: how to calculate it step by step
• How to run annual CAM reconciliation: process, timelines and dispute handling
• NetSuite CAM reconciliation automation