Radon Mitigation

Updated 2026-05-17

Radon mitigation refers to the processes and systems used to reduce elevated radon levels in existing buildings. When radon gas concentrations are found to be above acceptable limits, mitigation is necessary to protect occupants from the health risks associated with long-term exposure, primarily lung cancer.

Common mitigation techniques include:

• Sub-slab depressurization: This is the most common and effective method. It involves installing a vent pipe through the foundation floor into the soil beneath, connected to a fan that draws radon gas from below the house and vents it safely outside.
• Sealing cracks and openings: Sealing visible cracks and other openings in the foundation floor and walls can help prevent radon entry, though this alone is rarely sufficient for significant reductions.
• Increased ventilation: Improving the ventilation of a crawl space or basement can help dilute radon concentrations.

States often reference specific industry standards for radon mitigation, such as ANSI/AARST Multi-family Measurement and Mitigation Standards and ASTM E2121-12 ("Standard Practice for Mitigation Systems in Existing Low-Rise Residential Buildings"). These standards ensure that mitigation systems are installed effectively and safely.

The need for Radon Mitigation is often triggered by Radon Gas Requirements related to property sales or loan applications, particularly for VA Loan Entitlement, Certificate of Eligibility (COE), and Loan Guaranty Certificate (LGC).

References

1. 2026 VA Radon Testing: Required? Mitigation Costs Explained — valoannetwork.com
2. [PDF] State Multi-Family Radon Requirements State Certification — sosradon.org