How Commercial Real Estate Is Valued, and Why Values Move So Sharply

Commercial property valuation is arithmetically simple and behaves in ways that surprise people who have only owned a home. A building is worth the income it produces, divided by the yield an investor requires.

Both inputs move, and the division amplifies changes in the second one considerably.

Net operating income

Net operating income is rental income less the costs of running the building — maintenance, insurance, property taxes, management. It excludes financing costs and capital improvements, which is deliberate: it describes what the asset produces regardless of how it was funded.

It is more volatile than headline rent suggests. Leases expire and renew at market rates. Vacancy directly reduces income while costs continue. Operating costs move independently of rents, and insurance in particular has risen sharply in some regions.

The capitalisation rate

Divide net operating income by the price and you get the capitalisation rate — the unleveraged yield. Run it the other way, dividing income by a required cap rate, and you get a valuation.

Cap rates reflect what investors demand for the risk: the level of risk-free rates, perceived durability of the income, and the quality of the building and its location.

Why small changes hurt

Because it is a division, the effect is non-linear. A building producing steady income valued at a 5% cap rate is worth twenty times that income. At 6% it is worth about sixteen and a half times.

That is a fall of roughly a sixth from a single percentage point, with the building's income entirely unchanged. Cap rates move with interest rates and sentiment, which is why property values can drop sharply while the underlying tenants are still paying rent on time.

Debt magnifies it

Most commercial property is bought with substantial borrowing, and debt amplifies both directions.

A property bought with 60% debt that loses a sixth of its value has lost roughly 40% of its equity. If that decline pushes the loan-to-value ratio past a covenant, the lender may require additional equity or repayment.

The acute risk is refinancing. Commercial mortgages typically run for a term far shorter than the useful life of the building, so borrowers refinance repeatedly. A loan maturing when values are lower and rates are higher can require an equity injection simply to be refinanced at the same size — a demand for cash triggered by market conditions rather than by anything happening in the building.

Valuations lag reality

Property transacts infrequently and each asset is unique, so valuations depend on appraisals rather than observable prices.

Appraisals reference comparable transactions, which means they follow the market rather than lead it — and when transaction volume dries up, as it does when buyers and sellers disagree about value, there are few comparables to reference.

So reported values move more slowly and smoothly than underlying conditions. This is worth remembering when comparing property returns to listed markets: some of property's apparent stability is a measurement artefact.

The sectors behave differently

Treating commercial property as one asset class obscures more than it reveals; the segments have different drivers and different risks.

Lease length is the variable that most shapes risk. Long leases provide stable income and slow adjustment to rising market rents; short ones capture increases quickly and offer no protection when demand falls.

Where the risk actually sits

Property risk is often discussed as though it were borne by owners. Much of it sits with lenders, and through them with the banking system.

Commercial property lending is concentrated in particular institutions, and losses are correlated because valuations move together across a sector and region. That is why supervisors watch property exposure closely, and why difficulty in one property segment can become a question about bank capital rather than only about landlords.

For anyone assessing exposure, the question is not only who owns a building but who lent against it and on what terms — because the refinancing point, not the valuation date, is where problems tend to surface.

Repurposing is harder than it sounds

When a building's original use declines, conversion to another is frequently proposed and less frequently completed.

The obstacles are physical and financial. Floor plates designed for one use may be the wrong depth for another, leaving interior space without daylight. Plumbing and ventilation designed for a few concentrated cores must be redistributed. Structural loading, lift capacity and fire egress may all require modification.

The financial hurdle is that conversion competes against the value of the building as it stands. A conversion only proceeds if the finished value exceeds the current value plus the substantial cost of the work — which typically means it happens only after values have fallen far enough to make the arithmetic work.

What to look at

The last is the most commonly underestimated. A building that has not been reinvested in loses tenants slowly, then quickly.