What are average radon levels in Dunwoody, Georgia?

Average radon levels in Dunwoody range from 3.0 to 4.5 pCi/L based on local testing data. Dunwoody is in DeKalb County, which the EPA classifies as Zone 2 (moderate risk). Approximately 20-30% of tested homes in Dunwoody exceed the EPA action level of 4 pCi/L. Individual homes can vary significantly depending on foundation type and local soil conditions.

Is radon common in Dunwoody homes?

Yes. Dunwoody's location on the Piedmont geological province means the underlying rock produces radon gas. Testing data shows that roughly 1 in 4 to 1 in 3 Dunwoody homes test above 4 pCi/L. Homes with basements tend to have higher levels than slab homes, but both foundation types can exceed the EPA action level.

How much does radon testing cost in Dunwoody?

Professional radon testing in Dunwoody typically costs $125 to $250 for a 48-hour continuous radon monitor (CRM) test. DIY charcoal test kits are available for $15 to $40 plus lab fees. Professional CRM testing is recommended for real estate transactions because it provides hourly data and is harder to tamper with.

Does Dunwoody or DeKalb County require radon testing?

No. Neither Dunwoody nor DeKalb County requires radon testing for home sales or at any other time. Georgia has no statewide radon testing mandate. Testing is voluntary but strongly recommended, especially in areas like Dunwoody where a significant percentage of homes test above the EPA action level.

Radon in Dunwoody, Georgia: What Homeowners Need to Know

1. Why Dunwoody Homeowners Should Know About Radon

Dunwoody sits in northern DeKalb County on the Piedmont geological province. The bedrock here includes gneiss and granite formations that contain naturally occurring uranium. As uranium decays through radium, it produces radon gas that migrates upward through soil and enters homes through foundation cracks, construction joints, and gaps around pipes.

Much of Dunwoody's housing stock was built between the 1960s and 1990s, though newer construction continues throughout the city. The older ranch homes and split-levels that define neighborhoods like Dunwoody Village and Georgetown often have basements or crawl spaces that create direct pathways for radon entry. But even newer slab-on-grade homes are not immune.

Radon is odorless and invisible. Long-term exposure to elevated levels is the second leading cause of lung cancer in the United States. The only way to know whether your Dunwoody home has a radon problem is to test for it.

2. EPA Zone Designation for Dunwoody

Dunwoody falls within DeKalb County, which the EPA classifies as Zone 2. This designation means the predicted average indoor radon level for the county is between 2 and 4 pCi/L. The EPA considers this a moderate risk area, but that county-level average can be misleading for specific cities and neighborhoods.

Zone	Predicted Avg	Risk Level
Zone 1 (Highest)	Above 4 pCi/L	High
Zone 2 (DeKalb County / Dunwoody)	2-4 pCi/L	Moderate
Zone 3 (Lowest)	Below 2 pCi/L	Low

Moderate Risk Still Means Many Homes Are Above 4 pCi/L

A Zone 2 designation means the average is between 2-4 pCi/L, but averages include homes on both sides. In Dunwoody specifically, 20-30% of tested homes exceed the EPA action level. Two homes on the same street can have very different radon levels based on foundation type, soil permeability, and construction details. Testing is essential.

3. Neighborhoods with Higher Radon Potential

All Dunwoody homes should be individually tested, but certain neighborhoods show patterns of higher radon readings:

Dunwoody Village. The heart of the original Dunwoody community, with many homes dating to the 1970s and 1980s. These homes frequently have basements and crawl spaces that serve as direct radon entry points. The mature neighborhood sits on well-established soil over Piedmont bedrock, creating favorable conditions for radon accumulation.

Georgetown. Another established subdivision with homes primarily from the 1970s. Many Georgetown homes have partial or full basements. The combination of older construction (more settlement cracks, aging sealants) and below-grade living space creates ideal conditions for elevated radon.

Winters Chapel area. Located in the northern part of Dunwoody near the Gwinnett County line. The housing stock here is mixed, including both older ranch homes and newer townhome developments. Even the newer construction in this area can have elevated radon due to the productive geology underneath.

Perimeter area. The southern portion of Dunwoody near Perimeter Mall includes condos, townhomes, and single-family homes. Ground-floor and first-floor units in multi-family buildings can still have radon issues, particularly those built on slab foundations directly over soil. Upper floors generally have lower risk.

Check your specific zip code using our radon risk lookup tool for an area-level risk assessment.

4. Local Testing Data and Patterns

Aggregated testing data from radon professionals working in Dunwoody shows several consistent patterns:

Average test results in Dunwoody range from 3.0 to 4.5 pCi/L, placing the city at the higher end of DeKalb County's range.

Approximately 20-30% of tested homes exceed the EPA action level of 4 pCi/L.

Homes with basements consistently test higher than slab homes in the same neighborhood, often by 30-50%.

Winter testing (December through February) produces levels 40-60% higher than summer testing. Borderline summer results should be followed up with a winter retest.

Dunwoody's older housing stock is a factor in the testing data. Homes built in the 1960s through 1980s have had decades of foundation settling, which creates more cracks and gaps for radon to enter. However, this does not mean newer homes are safe. The geology is the primary driver, and it does not change based on construction date.

5. How to Test Your Dunwoody Home

Radon testing is straightforward and affordable. Here is the recommended approach for Dunwoody homeowners:

Choose Your Test Type

A short-term test (48 hours minimum) is good for initial screening. For real estate transactions, professional CRM testing is the standard. DIY charcoal kits cost $15-40 plus lab fees for a general check.

Place the Test Correctly

Test in the lowest livable level. For Dunwoody homes with basements, that means the basement, even if you do not use it daily. For slab homes, test on the main floor. Keep the test away from windows, exterior walls, and drafts. Maintain closed-house conditions during the testing period.

Interpret Your Results

Below 2 pCi/L: Low risk, retest every 2 years. Between 2-4 pCi/L: Consider a follow-up long-term test or mitigation. Above 4 pCi/L: The EPA recommends mitigation. Above 8 pCi/L: Prioritize mitigation promptly.

Many Dunwoody homeowners first learn about radon during a home sale. If you are buying or selling, read our guide on radon and basements to understand how below-grade spaces affect radon levels.

6. Mitigation Options for Dunwoody Homes

If your Dunwoody home tests above 4 pCi/L, mitigation is effective and typically completed in a single day. The right system depends on your foundation:

Slab or Basement

$1,200-$2,500

Sub-slab depressurization: a suction point through the foundation, PVC piping, and a fan that pulls radon from beneath the slab and vents it above the roofline.

Crawl Space

$2,500-$5,000

Sub-membrane depressurization: a sealed vapor barrier over exposed soil with active suction pulling radon from beneath the membrane and venting it outside.

Both systems achieve 90-99% radon reduction. A post-mitigation test confirms the system is performing as expected. Use our mitigation cost estimator to get a more specific estimate for your home.

Dunwoody Homeowners

With 20-30% of Dunwoody homes testing above the EPA action level, testing is not something to put off. A 48-hour test gives you a clear answer. If mitigation is needed, it is a one-day installation that solves the problem permanently. The cost is modest compared to the long-term health risk of breathing elevated radon.