Report: Billions of Dollars in Data Center Construction Risk Is Uninsured

Why It Matters

The coverage gap raises financing costs and limits capital formation for hyperscale data centers, while the aggregation risk threatens broader insurance market stability.

Key Takeaways

• Data‑center construction premiums could reach $10 bn in 2026.
• Insurers cover only 30‑50% of campus value, using PML limits.
• Multi‑carrier quota‑share programs are now standard for megaprojects.
• New capacity programs (Marsh Nimbus, Aon Lifecycle) cap at $3‑$4 bn.
• Site clustering creates aggregation risk, driving alternative‑capital insurance solutions.

Pulse Analysis

The data‑center boom is reshaping the construction‑insurance landscape. With S&P Global projecting more than 11,000 facilities and a $2 trillion insurable asset base, annual premiums could double the global aviation market’s output by 2026. Yet the traditional builders’ risk model, which once matched full replacement value, is being upended by campuses that now cost $5‑$25 billion. Insurers have shifted to probable maximum loss (PML) modeling, capping limits at $1.5‑$3.5 billion and leaving up to half of a project’s cost uncovered. This mismatch forces developers to retain risk on balance sheets and to assemble multi‑carrier quota‑share programs that spread exposure across several insurers.

To bridge the shortfall, specialty carriers have launched dedicated capacity facilities. Marsh’s Nimbus program offers up to $2.7 billion in limits, while Aon’s Data Center Lifecycle Insurance now tops $3.5 billion and extends coverage into the operational phase. These products provide a more coordinated approach, but even their ceilings fall well below the $10‑$30 billion value of the largest hyperscale sites. Consequently, owners, lenders, and equity partners are increasingly turning to alternative‑capital mechanisms—catastrophe bonds and insurance‑linked securities—to access the capital needed for full‑value protection.

The concentration of megasites in tornado‑ and hail‑prone zones amplifies aggregation risk, a concern that could reverberate across the broader reinsurance market. When multiple high‑value campuses sit within the same zip code, a single natural event could trigger losses that exceed the combined capacity of traditional carriers. This risk dynamic is prompting regulators and financiers to scrutinize underwriting practices more closely, as inadequate coverage can inflate borrowing costs and stall project timelines. As data centers account for an estimated 14% of U.S. power demand by 2030, the industry’s ability to secure robust, scalable insurance will be a decisive factor in sustaining its rapid expansion.