How do you calculate IGU seal failure exposure?

Multiply the number of at-risk IGUs by the average claim cost and by the expected failure share, then add any fixed campaign cost. With 680 at-risk units at $165 each and an 18% expected failure share, variable exposure is $20,196; adding a $12,500 fixed campaign gives $32,696 total.

What is a typical IGU seal failure rate?

Industry field data and ASTM E2190-tested production typically run well under 1% over the warranty period for good fabrication, but a contaminated sealant or spacer lot can push the expected failure share into the 10-25% range, which is why the default uses 18% for a known-suspect batch.

What does seal failure cost per IGU?

In this example the blended exposure works out to about $48.08 per at-risk IGU once you spread the variable claims and the fixed campaign over all 680 units, even though the average individual claim is set at $165.

Should I run a proactive reglaze campaign or wait for claims?

Compare the fixed campaign cost against the variable exposure: here the $12,500 campaign is well below the $20,196 in expected claims, and a proactive program also caps reputational and consequential-damage risk, which usually tips the decision toward acting.

What is the difference between seal failure exposure and warranty reserve?

Exposure is the expected total cost for a specific at-risk batch; a warranty reserve is the accounting provision you book against it. This tool sizes the exposure so finance can set a defensible reserve.

Why does desiccant or PIB matter to seal failure?

The desiccant absorbs internal moisture and the polyisobutylene (PIB) primary seal blocks vapor and argon migration; if either is contaminated or misapplied, units fog prematurely, which is the failure mode this exposure model is built to quantify.

Construction Products, Windows, Doors & Fenestration calculator

IGU Seal Failure Exposure Calculator

Insulating glass unit (IGU) seal failure is the single most common warranty claim in residential and commercial glazing, showing up as fog, condensation, or a milky haze between panes once the perimeter seal lets argon escape and moisture in. This calculator estimates your total dollar exposure across a population of at-risk units by combining how many IGUs sit in the suspect batch, the average cost to settle one claim, the share you actually expect to fail, and any fixed cost of running a proactive recall or reglaze campaign. Warranty managers, glazing fabricators, and IGU line quality engineers use it to size reserves before a known bad batch (bad PIB application, desiccant contamination, or a spacer lot problem) turns into uncontrolled field claims. Getting the number right tells you whether to ride it out reactively or fund a controlled replacement program.

What this calculator does

Estimate IGU seal failure exposure from at-risk units, expected claim cost, occurrence scope, and fixed campaign cost.
budgeting warranty or quality exposure for sealed glass units
It computes total expected warranty exposure for an at-risk IGU population as variable claim cost (units times cost per claim times expected failure share) plus a fixed campaign cost.

Formula used

Variable seal failure exposure = IGUs at risk of seal failure × average seal failure claim cost × expected seal failure occurrence share
Total IGU seal failure exposure = variable seal failure exposure + fixed seal failure campaign cost

Inputs explained

IGUs at risk of seal failure:
Average seal failure claim cost:
Expected seal failure occurrence share:
Fixed seal failure campaign cost:

How to use the result

Use it when a defective spacer, sealant, or desiccant lot is identified, or when field fog claims start clustering and you need to reserve dollars or justify a proactive reglaze.
The model assumes a single average claim cost; real claims vary widely between a simple sash swap and a full storefront unit with crane access, so treat the output as an expected value, not a per-claim guarantee.

Current U.S. benchmarks

U.S. housing starts run at 1,177k per year (Census, May 2026), down 8.7% from a year earlier, the demand driver for building products.

Common questions

How do you calculate IGU seal failure exposure? Multiply the number of at-risk IGUs by the average claim cost and by the expected failure share, then add any fixed campaign cost. With 680 at-risk units at $165 each and an 18% expected failure share, variable exposure is $20,196; adding a $12,500 fixed campaign gives $32,696 total.
What is a typical IGU seal failure rate? Industry field data and ASTM E2190-tested production typically run well under 1% over the warranty period for good fabrication, but a contaminated sealant or spacer lot can push the expected failure share into the 10-25% range, which is why the default uses 18% for a known-suspect batch.
What does seal failure cost per IGU? In this example the blended exposure works out to about $48.08 per at-risk IGU once you spread the variable claims and the fixed campaign over all 680 units, even though the average individual claim is set at $165.
Should I run a proactive reglaze campaign or wait for claims? Compare the fixed campaign cost against the variable exposure: here the $12,500 campaign is well below the $20,196 in expected claims, and a proactive program also caps reputational and consequential-damage risk, which usually tips the decision toward acting.
What is the difference between seal failure exposure and warranty reserve? Exposure is the expected total cost for a specific at-risk batch; a warranty reserve is the accounting provision you book against it. This tool sizes the exposure so finance can set a defensible reserve.

Last reviewed 2026-05-12.