How to Value an IOS Site
Industrial outdoor storage valuation is simpler than traditional CRE in some ways and more nuanced in others. The simplicity comes from the absence of building improvements that require depreciation and capital reserve modeling. The nuance comes from a market that lacks the comprehensive data infrastructure of office or multifamily, making comparable analysis more art than science in some cases.
Like all income-producing real estate, IOS value is primarily determined by the income it generates and the cap rate applied to that income. Understanding both components thoroughly is the foundation of IOS underwriting.
IOS Cap Rates by Market (2025)
Cap rates for stabilized IOS assets have compressed significantly since 2019, reflecting institutional capital inflows and the asset class's proven performance track record:
- Los Angeles / Long Beach: 4.75-5.5% — tightest caps nationally, reflecting port proximity premium and land scarcity
- Northern New Jersey / NYC Metro: 5.0-5.75% — port access, dense logistics demand, severely constrained supply
- Miami: 5.0-5.75% — international trade hub, growing Latin American logistics corridor
- Dallas: 5.5-6.25% — deep market, strong fundamentals, liquid transaction environment
- Seattle: 5.5-6.0% — port proximity, tech sector logistics demand
- Chicago: 5.5-6.25% — major intermodal hub, diverse institutional buyer pool
- Houston: 5.75-6.5% — energy cycle exposure adds risk premium vs coastal markets
- Atlanta: 6.0-6.75% — strong growth fundamentals, secondary market premium to primary
- Phoenix: 6.25-7.0% — growing market, less institutional liquidity than primary markets
- Nashville / Charlotte / Denver: 6.5-7.5% — emerging markets with less transaction history
- Savannah / Las Vegas: 7.0-7.75% — developing IOS markets, higher yield to compensate for thinner liquidity
Value-add and development opportunities can generate 8-12% yields on cost before stabilization, representing meaningful spreads over acquisition cap rates.
NOI Calculation for IOS
The IOS NOI calculation is straightforward:
Gross Rent: (Acres) × (Monthly Rent per Acre) × 12
Example: 5 acres × $5,500/ac/mo × 12 = $330,000 gross annual rent
Vacancy Allowance: In tight markets (2.5% national average), a 3-5% vacancy/credit loss allowance is reasonable. In markets with thinner demand, use 5-8%.
Example: $330,000 × 3% = $9,900 vacancy allowance
Effective Gross Income: $320,100
Operating Expenses: IOS operating expenses are typically 10-15% of effective gross income, covering:
- Property taxes (typically the largest expense; varies significantly by jurisdiction)
- Insurance (property and liability)
- Management (3-5% of gross rent if third-party managed)
- Maintenance (gravel, fencing, lighting repair)
- Snow removal / landscaping (market-dependent)
Example: $320,100 × 12% = $38,412 operating expenses
NOI: EGI — Operating Expenses = $320,100 − $38,412 = $281,688
Value at 6.0% Cap Rate: $281,688 ÷ 0.06 = $4,694,800
This simple example illustrates the IOS value proposition: 5 acres of industrial outdoor storage, leased at $5,500/acre/month to a creditworthy trucking company, is worth nearly $5 million at a 6% cap rate — with minimal building improvements driving that value.
Key Rent Assumptions by Market
Getting rent assumptions right is the most important step in IOS underwriting. Rents vary significantly by market, submarket, site size, and site quality. Using market averages without adjusting for submarket premiums or site-specific factors will produce inaccurate valuations.
Key factors that command rent premiums above market averages:
- Highway interchange visibility and direct access (0.25 mile premium: +10-20%)
- Existing hard-surface improvements (gravel vs. bare soil: +10-15%)
- Existing perimeter fencing and security lighting (+5-10%)
- Rail access or proximity to intermodal terminal (+10-15%)
- Port proximity in port markets (+15-25%)
- Large format (10+ acres) with outdoor amenities (+5-10%)
Factors that reduce rents below market averages:
- Flood zone exposure (-10-20%)
- Poor highway access, significant truck route limitations (-15-25%)
- Irregular site shape that reduces usable area (-5-10%)
- Adjacent incompatible uses (residential, recreational) (-5-10%)
- Environmental restrictions limiting stored materials (-10-20%)
What Institutional IOS Investors Look For
Institutional IOS investors — Alterra, Zenith, Triten, Realterm — underwrite to specific criteria that differ from smaller operators and value-investors:
- Minimum site size: typically 2+ acres; institutional deals often target 5-20+ acre sites
- Market position: primary or strong secondary IOS markets with demonstrated rent history and liquid transaction environment
- Lease structure: ideally NNN or modified gross leases with 3-5% annual rent escalators
- Tenant quality: preference for operating companies with auditable financial history; transportation, logistics, construction sector tenants are most common
- Zoning certainty: by-right outdoor storage permitted use preferred; conditional uses require additional risk premium
- Environmental clearance: Phase I ESA required; Phase II triggered by identified concerns
- Return requirements: development yields of 8-11% on cost for value-add and ground-up; acquisition at sub-7% cap for stabilized core assets
Common Underwriting Mistakes in IOS
The most common errors IOS investors make:
- Using market averages without submarket adjustment — rents vary 20-40% within markets based on location quality
- Underestimating property taxes — as IOS values have risen, assessment increases are catching up; model tax increases aggressively
- Assuming 0% vacancy — even in tight markets, vacant periods between tenants occur; always include a 3-5% allowance
- Ignoring site improvement costs — value-add sites may require significant gravel, fencing, and drainage investment before leasing
- Overestimating rent growth going forward — the 123% rent growth since 2020 was exceptional; underwrite 6-8% annual growth in strong markets, 3-5% in secondary markets
For AI-powered rent estimation and site analysis integrated into underwriting, join the CRE Intel waitlist. Also read our overview of the IOS market in 2025.