When two causes contribute to the same roof damage — one covered by your policy and one excluded — and why that combination can put your entire claim at risk in Colorado.
What Concurrent Causation Means
Concurrent causation occurs when two or more causes contribute to the same property damage — happening either simultaneously or in sequence. In roof insurance claims, the most common scenario involves a covered cause like hail or wind occurring alongside an excluded cause like normal wear and tear, poor maintenance, or pre-existing deterioration.
The question concurrent causation raises is straightforward: if both a covered cause and an excluded cause contributed to your roof damage, does your insurance pay? The answer depends on your specific policy language — and it is one of the most consequential coverage questions a Colorado homeowner can face, particularly on an older roof.
Why Concurrent Causation Matters in Colorado
Colorado’s Front Range sits in one of the most hail-active regions in the United States. Roofs here take repeated hits over their lifespan — which means that by the time a significant hailstorm occurs, most roofs have some degree of existing wear. That pre-existing condition gives carriers a potential foothold to argue concurrent causation and reduce or deny an otherwise valid claim.
This is not a theoretical concern. Concurrent causation disputes are a common feature of contested roof claims in Colorado Springs and Pueblo — particularly on roofs over 10 years old where the combination of age-related wear and storm damage is most likely to be present simultaneously.
How Policies Handle Concurrent Causation
How your policy responds to concurrent causation depends entirely on the specific language it contains. There are two fundamentally different approaches:
Policies Without an Anti-Concurrent Causation Clause
Under the traditional approach — and under Colorado’s efficient proximate cause doctrine — if a covered peril was the dominant or primary cause that set the loss in motion, coverage applies even if an excluded peril also contributed. A hailstorm that damages a roof with some pre-existing wear is still a hail claim. The carrier covers the storm damage and applies depreciation for the roof’s age and condition — but the claim is paid.
Policies With an Anti-Concurrent Causation Clause
Policies that include an anti-concurrent causation (ACC) clause take a more aggressive position. Under ACC language, if any excluded cause contributed to the loss — even as a minor factor — the carrier may deny the entire claim, regardless of whether a covered cause was also present. The concurrent existence of an excluded cause potentially voids coverage entirely, not just reduces it.
This is the distinction that makes concurrent causation one of the most significant coverage issues in Colorado roof claims. The same damage, on the same roof, after the same storm, can result in full coverage under one policy and a complete denial under another — depending solely on whether an ACC clause is present.
The Efficient Proximate Cause Doctrine in Colorado
Colorado recognizes the efficient proximate cause doctrine — a legal principle that provides meaningful protection to policyholders in concurrent causation situations.
Under this doctrine, when a chain of events leads to a loss, coverage is determined by identifying the dominant, efficient cause that set the chain in motion. If that dominant cause is a covered peril — hail, for example — coverage applies even if excluded perils contributed along the way.
In practical terms, this means that a carrier cannot automatically deny a hail claim simply because a roof also had some pre-existing wear. If hail was the primary cause that triggered the damage, Colorado courts have in many cases required coverage despite the presence of an excluded contributing factor.
However, the efficient proximate cause doctrine is not a blanket override of ACC clauses. Its application depends on the specific policy language, the specific facts of the loss, and how Colorado courts have addressed similar situations. It is a legal argument — one worth making when the facts support it — not a simple rule that guarantees coverage in every concurrent causation scenario.
Common Concurrent Causation Scenarios in Roof Claims
Concurrent causation disputes in Colorado roof claims typically arise in one of these situations:
Hail Damage on an Aging Roof
The most common scenario. A roof with 15 or more years of service sustains hail damage. The carrier acknowledges the storm occurred but argues that pre-existing granule loss, wear, and deterioration contributed to the damage — invoking concurrent causation to reduce or deny the claim. The homeowner’s position is that the hail caused new, identifiable damage regardless of the roof’s prior condition.
Wind Damage and Failed Seal Strips
Wind lifts or removes shingles on an older roof. The carrier argues that the seal strips had already deteriorated — an excluded maintenance issue — and that properly functioning seal strips would have resisted the wind. The concurrent causes are the wind event (covered) and the aged seal strips (excluded).
Ice Dam Damage and Inadequate Insulation
Ice dam water intrusion causes interior damage. The carrier argues that inadequate attic insulation — a maintenance or construction issue — allowed the heat escape that caused the ice dam, making the resulting damage a concurrent causation situation involving both the weather event and an excluded construction deficiency.
Hail and Pre-Existing Leaks
A roof with a known but unrepaired leak sustains hail damage. The carrier argues that the pre-existing leak — a maintenance failure — contributed to the interior damage claimed, creating a concurrent causation dispute even if the hail damage itself is not disputed.
How to Protect Your Claim Against Concurrent Causation Arguments
The best defense against a concurrent causation denial is documentation that establishes the storm as the clear, primary cause of identifiable new damage — making the carrier’s concurrent causation argument factually difficult to sustain.
Document Your Roof’s Pre-Storm Condition
Dated inspection records, maintenance receipts, and pre-storm photographs establish a baseline condition. If your roof was in reasonable condition before the storm and shows new damage consistent with hail impact afterward, the before-and-after record directly undermines a pre-existing damage argument.
Obtain Address-Specific Storm Data
Official hail size, wind speed, and storm path data for your specific address on the date of loss establishes that a qualifying covered event occurred. Without this foundation, concurrent causation arguments are easier to sustain. With it, the carrier’s position that the damage was primarily from pre-existing conditions becomes much harder to defend.
Get a Professional Inspection That Addresses Causation Directly
A professional inspection report that identifies damage patterns consistent with hail or wind impact — and explicitly distinguishes those patterns from pre-existing wear — directly counters the factual basis of a concurrent causation denial. The more specific and technical the causation documentation, the weaker the carrier’s concurrent causation argument becomes.
Know Your Policy Language
Whether your policy contains an ACC clause determines the legal framework for any concurrent causation dispute. If your policy does not contain ACC language, the efficient proximate cause doctrine is your strongest argument. If it does, the analysis is more complex and may require legal review. Knowing which situation you are in before the dispute escalates matters.
Common Concurrent Causation Questions
Can a carrier deny my entire claim because my roof was old?
Not automatically — and not legitimately under most policy frameworks. Age affects depreciation, not coverage. A 20-year-old roof that sustains new hail damage has a covered claim under most Colorado policies. What the carrier can do is apply higher depreciation to reflect the roof’s age and condition. Using age alone as a basis to deny coverage — rather than calculate depreciation — is a different argument, and one worth challenging.
What if I knew my roof had some issues before the storm?
Pre-existing issues complicate a claim but do not automatically defeat it. The question is whether the storm caused new, identifiable damage beyond what existed before. A professional inspection that separates pre-existing conditions from storm-caused damage provides the documentation needed to support coverage for the storm-related portion of the loss.
How do I know if my policy has an ACC clause?
Look in the exclusions section of your policy for language referencing “concurrent” causes, losses occurring “in any sequence,” or damage excluded “regardless of any other contributing cause.” If you see that language, your policy has an ACC clause. If you are unsure, ask your agent to point you to the concurrent causation language specifically — and consider having a professional review the policy before your next storm season.
Is concurrent causation the same as the anti-concurrent causation clause?
Not exactly. Concurrent causation is the situation — two causes contributing to the same loss. The anti-concurrent causation clause is the policy provision that determines how that situation is handled. Concurrent causation can occur under any policy. Whether it results in a denied claim depends on whether the policy contains an ACC clause and how Colorado law applies to that specific language.
How Claim Advocacy Helps With Concurrent Causation Disputes
Concurrent causation disputes sit at the intersection of policy interpretation, causation documentation, and Colorado insurance law. Having professional support on your side changes both the quality of your documentation and your ability to respond effectively when a carrier invokes concurrent causation.
- Pre-storm documentation — establishing a baseline roof condition before storm season that directly counters future pre-existing damage arguments
- Causation-focused inspection reports — documentation that explicitly separates storm damage from pre-existing wear, removing the factual basis for a concurrent causation denial
- Policy language review — identifying whether your policy contains an ACC clause and what that means for your specific claim
- Denial response strategy — determining whether to pursue re-inspection, appraisal, DOI complaint, or legal review based on the specific concurrent causation argument being made
- Attorney referral — connecting you with a Colorado insurance attorney when the efficient proximate cause doctrine or ACC clause interpretation requires legal expertise
Related Glossary Terms
- Causation
- Anti-Concurrent Causation Clause
- Exclusion
- Denial
- Adverse Action Letter
- Pre-Existing Condition
- Open Peril Policy
- Bad Faith
- Colorado Division of Insurance (DOI)
Dealing With a Concurrent Causation Dispute?
A concurrent causation denial is one of the more complex challenges in a roof insurance claim — but it is far from the final word. The right documentation and the right professional support can change the outcome. A free inspection is the most effective first step toward building the causation case your claim needs.
📞 Call to discuss your claim: (719) 210-8699
📧 Email: gerald@winik.io