When a hurricane makes landfall, it brings both wind and water. The wind is typically covered by a homeowners policy; the flood is typically excluded (and covered, if at all, by a separate National Flood Insurance Program policy). When both perils converge to cause a single loss—or when the damage from each cannot be cleanly separated—the legal question of which causation doctrine applies determines whether the insured recovers. Florida and Alabama have adopted materially different approaches, and the presence or absence of an anti-concurrent causation (ACC) clause in the policy adds another layer of complexity that practitioners must analyze before filing any claim.
I. The Two Competing Doctrines
A. Concurrent Causation
The concurrent cause doctrine (CCD) provides that coverage may exist when a covered peril operates as a concurrent cause of the loss—even if the covered peril is not the prime or efficient cause, and even if a non-covered or excluded peril also contributes to the same loss. Under pure concurrent causation, if an insured risk causes even part of the loss alongside an excluded risk, the entire loss is covered, or at minimum the covered portion is recoverable. This is a pro-insured doctrine.
B. Efficient Proximate Cause
The efficient proximate cause (EPC) doctrine asks which peril was the dominant, moving, and most significant cause of the loss. Under this framework, the loss is covered if the efficient proximate cause is a covered peril—even if excluded perils contributed along the chain of causation. Conversely, the loss is excluded if the efficient proximate cause is an excluded peril. This doctrine is more analytically demanding (identifying the "efficient" cause in a complex weather event requires expert analysis) but provides a more bounded framework than the concurrent cause doctrine.
II. Florida: Sebo and the Concurrent Cause Doctrine
A. The Decision
Sebo v. American Home Assurance Co., 208 So. 3d 694 (Fla. 2016), is the controlling Florida authority on concurrent causation in property insurance. John Sebo purchased a home in 2005. His all-risk policy, issued by American Home Assurance Company, covered the home against a broad range of perils. The home suffered from serious design and construction defects that caused water intrusion. Hurricane Wilma subsequently struck and caused additional damage. AHAC denied most of the claim, relying on the policy's exclusion for defective design and construction.
The jury found in Sebo's favor. The Second District reversed, concluding that coverage did not exist under an all-risk policy when multiple perils combined to cause a loss and at least one was excluded. The Florida Supreme Court quashed the Second District's opinion.
The Court held: "the concurrent-cause doctrine, not the efficient-proximate-cause doctrine, is the appropriate theory of recovery to apply when two or more perils converge to cause a loss and at least one of the perils is excluded from an insurance policy." The Court further explained that where "weather perils combine with human negligence to cause a loss, it seems logical and reasonable to find the loss covered by an all-risk policy even if one of the causes is excluded from coverage." The key factual predicate is the absence of a "reasonable way to distinguish the proximate cause of the loss"—when the perils are interdependent and their respective contributions cannot be cleanly segregated, concurrent causation applies.
Sebo's reasoning maps directly onto hurricane claims: when wind and flood converge—when the roof is opened by wind and then rain pours in, when storm surge arrives after wind has already compromised the structure—the perils act in concert, and the concurrent cause doctrine entitles the insured to coverage.
B. The Burden-Shifting Framework in Florida
Post-Sebo, Florida courts have developed a burden-shifting structure for concurrent causation claims:
- The insured bears the initial burden of demonstrating that a covered peril (wind) was a concurrent cause of the loss.
- If the insured makes that showing, the burden shifts to the insurer to prove that the covered cause either played no causal role (or a de minimis one) or that the covered cause was itself excluded under the policy.
Trial courts in Florida are instructed to craft jury instructions that first ask whether a single efficient proximate cause can be identified; if not, the concurrent cause instruction follows with the jury determining whether at least one covered cause was present.
III. Alabama: Efficient Proximate Cause and ACC Clause Enforcement
A. Alabama's Doctrinal Choice
Alabama follows the efficient proximate cause doctrine for first-party property insurance coverage disputes. Under State Farm Fire & Casualty Co. v. Slade, 747 So. 2d 293 (Ala. 1999), Alabama courts look to the dominant, moving cause of the loss rather than applying the more permissive concurrent cause approach. If the efficient proximate cause of the loss is a covered peril (wind), the claim is covered even if an excluded peril (flood) contributed along the causal chain. Conversely, if the efficient proximate cause is an excluded peril (flood or storm surge), the claim may be excluded even if wind played some role.
This framework has important implications for Alabama hurricane claims. Wind engineers and meteorologists become critical witnesses—the party whose expert most persuasively establishes which peril was the "dominant, moving cause" of the specific damage wins the doctrinal battle.
B. Anti-Concurrent Causation Clauses in Alabama
Alabama also permits enforcement of anti-concurrent causation (ACC) clauses, provided those clauses are clear and unambiguous. Slade, 747 So. 2d at 313–14. Under the ACC approach, if the policy contains language providing that an excluded peril will exclude coverage "regardless of any other cause or event contributing concurrently or in any sequence" to the loss, then the presence of an excluded peril in the causal chain—however minor—defeats coverage for the entire loss.
The ACC clause effectively overrides the efficient proximate cause doctrine: it contractually eliminates the "what was the dominant cause" inquiry and substitutes the question "was any excluded cause present at all?" When the answer is yes—and flood, storm surge, and earth movement are all paradigmatic excluded causes in standard homeowners policies—the ACC clause extinguishes the claim.
IV. Anti-Concurrent Causation Clauses: Analysis and Challenges
A. Typical ACC Language
Standard ACC clauses appear in the exclusions section and read approximately as follows: "We do not cover loss to property described in [this section] caused directly or indirectly by any of the following. Such loss is excluded regardless of any other cause or event contributing concurrently or in any sequence to the loss."
The Supreme Court of Florida has confirmed that where an ACC clause applies to the specific coverages at issue, the concurrent cause doctrine does not save the claim. In Security First Insurance Co. v. Czelusniak, 305 So. 3d 717 (Fla. 3d DCA 2020), the Third District upheld enforcement of an ACC clause in a case involving water entering through exterior walls—the court found that the ACC clause's plain language excluded the entire loss because an excluded cause was present, regardless of the concurrent cause doctrine.
Sebo itself did not involve an ACC clause, which is precisely why the concurrent cause doctrine applied. This distinction is critical: Sebo is the default rule in the absence of an ACC clause; the ACC clause is the insurer's contractual override of that default.
B. Grounds for Challenging ACC Clauses
Plaintiffs' counsel should scrutinize every ACC clause for the following potential vulnerabilities:
Ambiguity. An ACC clause that is ambiguous as to which excluded perils it covers, or whose scope is uncertain as applied to the specific facts, will be construed against the insurer under Florida's canon of contra proferentem. The clause must clearly and unambiguously express the intent to exclude coverage regardless of concurrent causes.
Scope limitations. The ACC clause must apply to the specific exclusion invoked. If the insurer relies on a flood exclusion with ACC language to deny a wind claim, confirm that the ACC language in the policy expressly applies to the flood exclusion—some policies include ACC language in some exclusions but not others.
Valued Policy Law (Florida). Florida's Valued Policy Law (VPL), Fla. Stat. § 627.702, requires that an insurer pay the face amount of a policy when an insured structure is a total loss from a covered peril. Courts have held, however, that the VPL does not apply when a total loss is caused by a combination of covered and excluded perils (wind and flood), unless the insured can prove that wind alone caused the total loss before storm surge arrived.
Public policy (limited). Some jurisdictions have declined to enforce ACC clauses as contrary to public policy, particularly where they effectively render coverage illusory in common weather-event scenarios. Florida and Alabama courts have not broadly adopted this argument, but the illusory coverage theory may be viable in extreme cases where the ACC clause eliminates virtually all coverage for catastrophic weather events.
V. Burden of Proof: Segregating Wind from Flood
Both Florida and Alabama require the insured to prove causation. In a concurrent-cause state like Florida without an ACC clause, the insured must show that a covered peril was a concurrent cause of the loss. In an EPC state like Alabama, the insured must show that a covered peril was the dominant, efficient cause. In both states, when an ACC clause applies, the inquiry shifts: the insurer must prove the presence of an excluded cause, and once it does, the burden may shift back to the insured to prove that the covered-peril portion of the loss can be segregated.
Engineering and meteorological expert testimony is indispensable. The standard approach involves:
- A wind forensic engineer who inspects the structure, analyzes debris patterns, roof failure modes, and storm-surge elevation data to identify which damage predated the storm surge arrival;
- A meteorologist who can establish wind speeds and storm surge timing at the specific property during the storm's passage; and
- A damages allocation expert who separates wind damage from flood damage to the extent feasible.
The "Wayne Rogers" approach—named after a series of post-Katrina decisions—asked courts to apportion covered and excluded losses; subsequent Florida decisions have refined this into the burden-shifting framework described above.
VI. Practice Notes
Review the policy before the claim is filed. Identify every exclusion, including the specific ACC language attached to each exclusion. Map the ACC clause scope against the actual perils at issue.
Order a wind and flood engineering analysis immediately. Evidence of pre-surge wind damage degrades rapidly. Roof debris, interior damage patterns, tree fall direction, and wind-driven rain stains must be documented before cleanup and remediation destroy them.
Invoke the Valued Policy Law where applicable. In Florida, if the structure was a total loss, investigate whether wind damage was the exclusive or dominant cause of the total loss, which triggers the VPL's mandatory full-policy-limit payment obligation.
*Plead Florida claims under Sebo and the CCD by default, then address the ACC clause.* If the policy lacks a qualifying ACC clause, the concurrent cause doctrine governs and the insured's burden is lighter. If an ACC clause is present, develop the ambiguity and scope arguments before and during discovery.
In Alabama, build the EPC record. Develop expert testimony that identifies wind as the efficient proximate cause—the damage that came first, was most severe, and that set in motion whatever subsequent excluded perils contributed to the loss.
VII. Conclusion
The wind-versus-flood causation dispute is, at its core, a question of which doctrinal framework applies and how the insurer's policy language modifies that framework. Florida and Alabama start from different baseline doctrines, but both permit insurers to override those doctrines with enforceable ACC language. Plaintiffs' counsel must engage this analysis at the earliest stage of the claim—before the engineering evidence is compromised, before the demand is framed, and before the policy language is assumed rather than analyzed.
Talk to Yates Anderson
If you are litigating a matter in this area — or weighing whether to — the working analysis above only goes so far. Request a case evaluation and a Yates Anderson attorney will respond within one business day.
Informational only. Not legal advice. No attorney-client relationship is created by reading this post. Consult a licensed attorney in your jurisdiction.