Commercial Real Estate Investors Face Indefensible Stable-Income Assumption After Disasters

Albert Slap, a real estate professional and founder of RiskFootprint, asserts that the common practice of treating net operating income as stable in commercial real estate underwriting, even for coastal properties vulnerable to floods or wind events, is no longer defensible. According to Slap, a single disaster can eliminate cash flow for months, yet many investors fail to model the impact on debt service when a property sustains major damage and goes offline. This oversight, he argues, exposes investors to risks they cannot see.

The stable-NOI assumption breaks down under scrutiny. Slap illustrates with a coastal commercial property generating $1.2 million in annual NOI and $900,000 in annual debt service, which appears serviceable on paper. However, using Hazus, FEMA's publicly available engineering model, a 500-year coastal flood scenario may show 12% structural damage, 8% contents damage, and nine months of restoration time. NOI drops by 75%, wiping out the ability to cover debt service. Adding structural and contents damage costs and factoring in uninsured losses that drain cash reserves pushes the stressed debt service coverage ratio below 1.00, meaning the borrower cannot service debt during restoration. Traditional underwriting would not have caught this.

The problem compounds in markets where insurance is tightening. Slap describes an environment where hazard frequency is rising, deductibles are increasing, exclusions are expanding, premiums are volatile, and business interruption coverage is shrinking—all simultaneously. Each variable erodes the financial cushion investors historically relied on to absorb event-driven losses.

Slap argues that quantifying hazard exposure should begin with Expected Annual Loss calculations, a metric that translates probabilistic hazard data into annualized financial terms. Using FEMA's National Risk Index building-specific EAL rates, investors can estimate what a given hazard costs a property on average each year. For a building with a $50 million replacement cost and a hurricane wind EAL rate of $444 per million dollars of value, the estimated annual loss is roughly $112,600. Over a 10-year hold period, that figure exceeds $1 million, before accounting for contents losses, business interruption, or reputational damage to tenants. “This is ROI-ready intelligence,” Slap says. For investors evaluating coastal acquisitions, he contends this natural hazard risk assessment should be standard, not supplemental. The question is not whether a property will face a hazard event, but how much that event is likely to cost and whether the investment thesis survives it.

Slap draws a distinction between the sustainability framing that dominated coastal real estate conversations previously and the ROI-driven approach he sees gaining traction now. “Every sustainability or resilience action has a cause and an effect,” he says. “The cause is the decision to invest. The effect is the benefit—reduced losses, improved continuity, lower operating costs, or enhanced market value.” That framing makes resilience investments defensible to investment committees, lenders, and partners. Investors asking whether a resilient retrofit will pay back need quantified exposure data to answer the question. Without it, Slap says, decisions default to intuition, and intuition cannot substitute for risk modeling in a market where hazard severity is accelerating.

Investors who integrate hazard modeling into acquisition underwriting will identify impaired assets before purchase, price risk more accurately, and make capital improvement decisions with a clearer cost-benefit basis, according to Slap. Those who do not will continue to discover hazard-driven losses after the fact.

RiskFootprint's platform aligns with the ASTM International Property Resilience Assessment Standard (E 3429-24), structuring hazard analysis across three stages: hazard exposure modeling, vulnerability and value-at-risk assessment, and feasible mitigation measures with cost-benefit analysis. The platform covers more than 34 hazard exposure types for every U.S. property and incorporates multiple flood models, including Swiss Re/Fathom pluvial, fluvial, and coastal data, FEMA FIRM maps, NOAA SLOSH storm surge, and NOAA/NASA King Tide projections. “If the comparison yields a positive number, then the Benefit/Cost owner/investor will have a reasonable basis to investigate the investment in risk mitigation measures in greater detail,” Slap says of the cost-benefit stage. For coastal CRE investors, hazard-driven financial stress testing is now available as an automated input rather than a custom consulting engagement. Slap says pressure from lenders and secondary markets to require this type of analysis is already building.