One of the most common misconceptions about radon is that new homes are safe from it. Builders focus on structural integrity, energy efficiency, and aesthetics, but radon prevention is often an afterthought. Even homes built with radon-resistant features need post-construction testing to verify they are actually working.
1. The "New Home = Safe" Myth
New homes can have radon levels just as high as older homes, and in some cases higher. Modern energy-efficient construction creates tighter building envelopes that reduce natural ventilation and can trap radon at higher concentrations. The geology beneath a new subdivision is the same geology that has been producing radon for millions of years.
The Numbers
Approximately 1 in 5 newly constructed homes in radon-prone areas of Georgia test above the EPA action level of 4.0 pCi/L. This is comparable to the rate found in older housing stock. Building age is not a reliable predictor of radon levels.
2. Radon-Resistant New Construction Features
The EPA developed a set of guidelines called Radon-Resistant New Construction (RRNC) that builders can incorporate during construction. These features are inexpensive to include during the build phase (typically $500 to $1,000 additional).
- Gas-permeable layer: 4 inches of clean, coarse gravel beneath the slab allows soil gas to move freely to a collection point.
- Vapor barrier: A polyethylene sheet over the gravel layer blocks radon from seeping through the slab.
- Vent pipe: A 3 or 4 inch PVC pipe runs from the sub-slab gravel layer up through the house and out through the roof.
- Sealed foundation: Cracks, joints, and penetrations in the foundation are sealed to reduce radon entry points.
- Junction box: An electrical junction box in the attic allows easy connection of a fan if the passive system needs to be upgraded.
3. Georgia Building Codes and Radon
Georgia's building code references the International Residential Code appendix on radon-resistant construction, but adoption and enforcement vary by jurisdiction. Some Georgia counties in EPA Zone 1 have adopted RRNC requirements, while many others have not. This means that even in high-risk areas, not all builders include radon-resistant features.
As a buyer, you cannot assume that your new home was built with radon protection unless you specifically requested it or the builder confirms it in writing. This makes post-construction testing especially important.
4. When to Test Your New Home
Testing Timeline for New Construction
- Before closing (if possible): Test during the final walk-through period. Results give you leverage if mitigation is needed.
- Within 30 days of occupancy: If pre-closing testing was not possible, test as soon as you move in.
- After settling in (3 to 6 months): A follow-up test after the home has been lived in for a few months can reveal changes as the foundation settles and usage patterns establish.
- 1 year after construction: Foundation settling, landscaping changes, and seasonal patterns can all affect radon levels during the first year.
5. Converting Passive to Active Systems
If your new home has RRNC features but testing reveals elevated radon, converting the passive system to an active system is straightforward and cost-effective. The process involves installing an inline fan on the existing vent pipe, typically in the attic. The fan creates active suction beneath the slab, dramatically improving radon reduction from 30 to 50% (passive) to 95%+ (active).
The conversion typically costs $300 to $800 and takes a few hours. The electrical junction box installed during construction makes fan installation quick and clean. Learn about active sub-slab suction systems and our radon-resistant new construction services. For a comprehensive look at RRNC in Georgia, see our RRNC guide. Also learn about short-term vs. long-term testing options.
6. Conversations with Your Builder
If you are purchasing new construction in Georgia, ask your builder these questions before committing.
- Are RRNC features included in the build? If not, can they be added?
- What EPA zone is the building site in?
- Will the builder test for radon before closing?
- If radon is elevated, will the builder install an active system under warranty?
7. Protecting Your Investment
Action Steps for New Home Buyers
- Request RRNC features in your purchase agreement
- Test before or immediately after closing
- If levels are elevated, convert passive system to active or install full mitigation
- Retest after 1 year to verify long-term levels
- Keep all radon documentation for future resale
Frequently Asked Questions
Test Your New Georgia Home
New construction needs testing too. Schedule professional radon testing for your new home today.
