The second article in the Self Storage Basics series. Read How Self Storage Works as a Business first if you are new to the sector.
Patrick Wood, JBW Commercial | September 2, 2026
Why the vocabulary matters
Self storage has a working language of its own, and most of it is borrowed from nowhere else in real estate. A broker will quote you rent per square foot when the tenant pays per unit. A lender will ask about economic occupancy when the manager reports physical occupancy. An offering memorandum will describe a facility as stabilized when a third of the rent roll is on a discount. None of this is deliberately confusing, but it does mean a newcomer can sit through a full conversation and come away with the wrong number.
This article covers the terms you will hear most often, grouped by where they come up: the building, the rent roll, the operations, and the transaction. Each is defined the way a Canadian operator or broker would use it.
Measuring the building
Gross building area (GBA) is the total footprint of the building, including hallways, offices, elevators and mechanical space. It is what the municipality and the insurer care about.
Net rentable square feet (NRSF) is the total area inside the units that a tenant can rent. It excludes hallways, the office, loading areas and anything else that does not earn rent. NRSF is the denominator for nearly every metric in the business: rent per square foot, price per square foot, and occupancy by area. When you compare two facilities, compare them on NRSF.
Efficiency is NRSF divided by GBA. A single-storey drive-up facility with no interior hallways can run above 90 per cent. A multi-storey climate controlled building with wide corridors, elevators and a large office is often 70 to 80 per cent. The gap is why two buildings of the same size can have very different income.
Unit mix is the schedule of unit sizes and types in the facility: how many 5 by 5s, 5 by 10s, 10 by 10s, 10 by 20s and so on, and how many of each are climate controlled, standard interior or drive-up. Unit mix determines the average rent per square foot the facility can achieve and how well it matches local demand. It matters far more than total unit count.
Drive-up units open directly to the outside, so a tenant can back a vehicle to the door. Interior units are accessed through a hallway. Climate controlled units sit inside a heated and cooled envelope, which in most of Canada means heated in winter and humidity managed in summer. They rent at a premium and cost more to build and operate.
Parking or vehicle stalls are outdoor spaces for cars, boats, trailers and RVs. They are counted as units and their rent is counted as income, but they are not included in NRSF. Stall counts are also fluid, because operators add and remove them as the lot allows, so parking is best reported as stalls rented rather than as an occupancy percentage.
Reading the rent roll
Physical occupancy is the share of units, or of NRSF, that are currently rented. It is the figure a manager reports and the one most often quoted in a listing. It says nothing about what those tenants are paying.
Economic occupancy is actual rent collected divided by the rent the facility would earn if every unit were rented at the current street rate. It captures vacancy, discounts, concessions and delinquency all at once. A facility can be 95 per cent physically occupied and 78 per cent economically occupied. Lenders and experienced buyers underwrite on the economic figure.
Street rate is the price a new tenant pays today for a given unit size. In-place rate is what existing tenants are actually paying, on average, for the same size. The gap between the two is one of the first things a buyer looks at, because it signals how much rent growth is available without raising street rates at all.
Rate per square foot is annual rent divided by the square footage of the unit. A 10 by 10 renting at $180 a month is $2,160 a year on 100 square feet, or $21.60 per square foot. Operators use this figure because it lets them compare a locker with a drive-up bay and one facility with another.
Concessions are move-in incentives, most commonly a first-month discount or a reduced introductory rate for a set period. They are normal in lease-up and in competitive markets, but a rent roll heavy with concessions is one where the in-place rate is being flattered by promotional pricing that will roll off.
Delinquency is rent owed but not paid. Storage delinquency is measured in days past due, and provincial lien legislation sets out how long a tenant can be in arrears before the operator can lock out the unit and eventually sell the contents. A later article in this series covers how that varies by province.
Length of stay is how long the average tenant remains. It is the reason month-to-month tenancies produce stable income, and it varies by market and unit type. Commercial tenants and larger units tend to stay longer.
Running the facility
Lease-up is the period from opening to stabilization, when a new facility is filling units for the first time. Absorption is the pace at which it fills, usually expressed as units or square feet per month. Both are covered in detail later in the series.
Stabilized describes a facility that has reached a steady-state occupancy, typically in the high 80s to low 90s per cent physical, with rents at or near market and no more than normal turnover. The word is used loosely in listings, so ask how it is being defined.
Revenue management is the practice of setting street rates by unit size and demand, and raising existing tenants’ rates on a schedule, usually annually and sometimes more often. It is the main lever behind income growth at professionally run facilities and the main thing an absentee owner tends not to do.
Ancillary income is everything other than unit rent: tenant insurance or protection plans, administrative fees, late fees, retail sales of boxes and locks, and parking. Tenant insurance is the largest and highest margin piece.
Third-party management means hiring an operator to run the facility under its brand and systems for a fee, typically a percentage of revenue with a monthly minimum. Remote management means running the facility without onsite staff, using a call centre, online rentals, keypad access and cameras. Hybrid models combine part-time onsite presence with remote support.
Break-even occupancy is the occupancy at which revenue covers operating expenses and debt service. It is the number that tells you how much cushion a facility has.
The transaction
Net operating income (NOI) is total revenue less operating expenses, before debt service, income tax and capital expenditures. It is the number a facility is valued on. Buyers normalize the seller’s expenses to what a new owner would actually incur, including a management fee, market property tax and current insurance, before relying on it.
Cap rate is NOI divided by price, expressed as a percentage. A facility producing $600,000 of NOI sold for $10 million trades at a six per cent cap rate. Lower cap rates mean higher prices. Cap rates in Canadian storage vary by market, quality and size, and are covered in the valuation article in this series.
Price per rentable square foot is the sale price divided by NRSF. Alongside cap rate, it is the standard way to compare storage transactions. Price per unit is not a reliable measure, because unit sizes vary too widely between facilities for the figure to mean anything.
Trailing twelve months (T-12) is the operating statement for the most recent twelve months. Buyers and lenders want the T-12, not a budget or a pro forma, because it shows what the facility actually did.
Pro forma is a projection of future income and expenses, usually prepared by the seller or broker. It is a useful starting point and not a substitute for the T-12.
Loan-to-value (LTV) is the mortgage amount divided by the appraised value. Debt service coverage ratio (DSCR) is NOI divided by annual mortgage payments. Canadian lenders on storage typically look for a DSCR comfortably above 1.25 and set LTV accordingly. The financing article later in the series goes further.
Opinion of value or broker opinion of value (BOV) is a broker’s estimate of what a facility would sell for in the current market, based on NOI, comparable transactions and market conditions. JBW Commercial prepares opinions of value for Canadian storage owners. It is not an appraisal, which is prepared by an accredited appraiser and is what a lender relies on.
Putting it together
Here is how these terms show up in a single sentence from a real listing: “A stabilized 48,000 NRSF facility at 91 per cent physical occupancy with an in-place rate of $19.40 per square foot and a T-12 NOI of $545,000, offered at a 6.25 per cent cap rate.” A newcomer now knows to ask what the economic occupancy is, where the street rate sits relative to $19.40, whether the NOI includes a management fee, and how the seller is defining stabilized.
The next article in the series steps back to the Canadian market as a whole: how much storage exists, who owns it, where the institutional capital is going and what that means for a first-time buyer.
This article is general educational commentary and is not investment, legal, accounting or tax advice. Patrick Wood is a commercial real estate professional and not a financial advisor. Readers should obtain independent advice before acting on any information here.
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