2026-05-03 · 4 min read
Radon Mitigation in Des Moines, IA: Why Iowa Has America's Most Aggressive Radon Program
Iowa has the highest average indoor radon of any state. Des Moines homeowners face above-average risk — and Iowa has mandatory contractor licensing to protect them.
Iowa's Exceptional Radon Risk
Iowa's position at the top of every national radon ranking isn't a statistical fluke — it's geology. The state sits on a complex of glacial till, loess deposits, and carbonate bedrock with among the highest uranium concentrations in the Midwest. Radon generated at depth moves efficiently through Iowa's permeable soils and enters homes across virtually every county.
Iowa averages approximately 8.5 pCi/L indoors — more than six times the national average of 1.3 pCi/L and the highest of any state in the country. The Iowa Radon Program, operated by the Iowa Department of Public Health, has been one of the most active state radon programs in the country for this reason.
Des Moines Specifically
Polk County and the surrounding metro area — Ankeny, Urbandale, West Des Moines, Clive, Johnston — are uniformly in EPA Zone 1. Sub-slab conditions in the Des Moines metro vary:
- Glacial till: Common in most areas; clay-heavy, which can restrict pressure field extension and may require the GX3 fan rather than the standard XP201
- Loess overlying till: Very fine, silty material with low permeability; can be challenging for standard sub-slab depressurization
- River floodplain soils: Near the Des Moines and Raccoon Rivers, sandy alluvial soils provide better permeability
Because sub-slab conditions vary significantly, a professional sub-slab communication test before finalizing the system design is important in Des Moines. A reputable contractor will do this assessment before specifying fan size and suction point locations.
Iowa's Licensing Program
Iowa's mandatory contractor licensing is among the more rigorous in the country, requiring:
- Completion of an approved radon contractor training course
- Passing an Iowa-specific licensing exam
- Submitting proof of insurance
- Annual license renewal
Verify your contractor's Iowa Radon Program license before hiring. The Iowa Radon Program maintains a searchable online directory. An unlicensed contractor is not legally authorized to perform mitigation work in Iowa.
Find certified mitigators in Des Moines → | Iowa radon cost guide →
Frequently Asked Questions
Does Des Moines have high radon?
Yes. Iowa has the highest average indoor radon of any US state — approximately 8.5 pCi/L. Polk County (Des Moines) is in EPA Zone 1. Iowa testing surveys show that a majority of homes exceed the 4.0 pCi/L action level, and many exceed 10 pCi/L.
How much does radon mitigation cost in Des Moines?
Des Moines homeowners typically pay $900–$1,600 for a standard system. Iowa has a well-developed contractor market given the state's radon focus. Clay-heavy sub-slab conditions — common in Iowa — may require a step-up to a GX3 fan and could push costs to $1,400–$2,000.
Is radon contractor licensing required in Iowa?
Yes — Iowa requires radon contractors to hold a state license issued by the Iowa Radon Program. This is one of the more rigorous state licensing programs in the country. Verify your contractor's Iowa license before scheduling work.
Find a Certified Mitigator Near You
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