Quick Answer
Average radon mitigation cost: $1,200-1,800 for a standard basement system.
- •Simple slab system: $800-1,500
- •Standard basement (1-2 suction points): $1,200-1,800
- •Complex multi-level system: $1,500-2,500
- •Crawl space membrane system: $1,000-2,000
Installation takes 3-6 hours. Systems last 10-15+ years with minimal maintenance.
What Is Radon Mitigation?
Radon mitigation is the process of reducing radon gas levels in your home using a mechanical system. The most common method—used in 90%+ of installations—is called sub-slab depressurization(also known as soil suction or active soil depressurization).
How Sub-Slab Depressurization Works:
Contractor drills through your basement floor
They create a 4-6 inch hole through the concrete slab into the soil beneath. This becomes the suction point where radon-laden air is pulled from under your foundation. For larger homes or complex foundations, multiple suction points may be needed.
PVC pipe vents radon above your roofline
A 3-4 inch PVC pipe runs from the suction point up through your home to vent above the roofline (usually 12+ inches above the roof edge). This safely exhausts radon into outdoor air where it disperses harmlessly. The pipe can run inside a closet, along exterior walls, or through the garage.
Specialized fan creates continuous suction
A radon-specific fan (rated for continuous outdoor use) mounts in your attic or outside the home. It runs 24/7, creating negative pressure beneath your foundation. This pulls radon gas out before it can enter your living space. Fan noise is minimal—similar to a refrigerator running.
Monitoring device tracks system performance
A U-tube manometer (pressure gauge) is mounted in your basement. It visually shows that the fan is working by displaying the pressure differential. If the fan fails, you'll see it immediately and can call for service.
How effective is this? Sub-slab depressurization systems reduce radon by 90-99%. The average home drops from 8-10 pCi/L down to 0.5-2 pCi/L after installation. Systems work immediately—radon levels start dropping within hours of turning on the fan.
Why DIY Radon Mitigation Usually Fails
Radon enters homes through complex pathways—foundation cracks, sump pits, block wall cavities, drain tiles. Professional contractors use diagnostic tools (pressure field extension testing, sub-slab communication tests) to identify the optimal suction point locations.
DIYers guess at placement. If you guess wrong, you might reduce radon in one area while increasing it in another, waste $200-500 on materials with nothing to show for it, or create a system that fails after soil conditions change. At 8 pCi/L, every month you delay proper mitigation = another month of radiation exposure. Get it done right the first time.
Radon Mitigation Cost Breakdown
Radon mitigation costs vary based on your home's foundation type, size, and the number of suction points required. Here's what you'll pay for the most common system types:
Average Costs by System Type:
Simple Slab-on-Grade System
Single-story home, 1 suction point, slab foundation
Best for: Ranch homes, condos, single-level construction with straightforward foundation access
Standard Basement System
1-2 suction points, poured concrete foundation
Best for: Most 2-story homes with full basements, standard construction, rectangular floor plan
Complex Multi-Level System
3-4 suction points, block walls, multiple foundation types
Best for: Large homes (3,000+ sq ft), split-level homes, additions with different foundation types, block wall foundations requiring multiple suction points
Crawl Space Membrane System
Plastic membrane sealing + sub-membrane depressurization
Best for: Homes with dirt-floor crawl spaces, pier-and-beam foundations, requires heavy-duty membrane covering entire crawl space floor
What's included in these prices:
- • All materials (PVC pipe, fan, sealants, hardware)
- • Labor for drilling, installation, and testing
- • Manometer (pressure gauge) for monitoring
- • Fan warranty (typically 3-5 years)
- • Post-installation testing (some contractors)
What Affects Your Specific Cost?
Foundation Type
Cheapest: Poured concrete slab (easy to drill, predictable suction)Mid-range: Poured concrete basementMost expensive: Block wall foundations (may need 3-4 suction points due to hollow cavities) or homes with multiple foundation types
Number of Suction Points
Most homes need 1-2 suction points. Large homes (3,000+ sq ft), split-level designs, or homes with complex floor plans may need 3-4 points. Each additional suction point adds $300-500 to the cost.
Geographic Location
Labor rates vary significantly by region. High-radon states (Iowa, Colorado, Pennsylvania) have more contractors and competitive pricing. Low-radon states have fewer specialists and higher prices. Urban areas cost 10-20% more than rural areas due to higher labor rates.
Aesthetic Routing
Standard installation: Exposed PVC pipe (painted to match) runs along exterior or through garage. Premium installation: Pipe hidden inside walls, closets, or chases. Add $200-500 for concealed routing.
Soil Conditions
Sandy or gravelly soil: Easy suction, may need only 1 point Clay or rocky soil: Harder to create vacuum, may need 2-3 points High water table: May require sump pump integration (add $200-400)
Annual Operating Costs
For perspective: $150/year = $12.50/month. Less than a Netflix subscription to protect your family from the #1 cause of lung cancer among non-smokers.
Radon Mitigation Costs by City
Labor rates and contractor availability vary significantly by location. Here's what homeowners actually pay in major US cities:
Denver, CO
EPA Zone 1 • 6.2 pCi/L avg
Higher costs due to altitude (stronger fans needed), rocky soil requiring multiple suction points, and high demand from Zone 1 designation
Chicago, IL
EPA Zone 1 • 5.2 pCi/L avg
Standard pricing due to competitive market, many contractors, mostly poured concrete foundations
Philadelphia, PA
EPA Zone 1 • 5.1 pCi/L avg
Older housing stock (many pre-1950 homes) with stone foundations requires more complex systems
Minneapolis, MN
EPA Zone 1 • 5.5 pCi/L avg
Cold climate installations require additional weatherproofing, higher labor rates in metro area
Phoenix, AZ
EPA Zone 2 • 3.1 pCi/L avg
Many slab-on-grade homes (simpler installations), but fewer contractors due to lower Zone designation
Portland, OR
EPA Zone 2 • 3.5 pCi/L avg
High labor rates, many crawl space homes requiring membrane systems, wet climate considerations
San Diego, CA
EPA Zone 2 • 2.8 pCi/L avg
Premium labor rates (highest in the country), fewer contractors due to lower radon prevalence
Houston, TX
EPA Zone 3 • 1.2 pCi/L avg
Lower costs due to slab construction prevalence, but very few contractors (low demand)
Pro tip: High-radon states (Zone 1) often have MORE competitive pricing despite higher demand because there are more certified contractors competing for business. Low-radon states (Zone 3) may have higher prices due to limited contractor availability, even though radon is less common.
Get Free Radon Mitigation Quotes
Connect with NRPP-certified radon mitigation contractors in your area. Get 2-3 quotes, compare warranties and pricing, choose the best fit for your home.
Request Free Quotes →Average response time: 24-48 hours • Most contractors offer free in-home estimates • No obligation
Do I Need Radon Mitigation?
The EPA recommends mitigation if your radon test shows levels at or above 4 pCi/L. But the decision isn't always black and white. Here's how to decide:
10+ pCi/L: Urgent Action Required
At 20 pCi/L, your lung cancer risk is 35-40 times higher than the national average. This is a health emergency requiring immediate professional mitigation.
✓ Contact 2-3 certified contractors TODAY ✓ Many offer emergency installations within 48-72 hours ✓ Avoid spending extended time in basement until system is installed ✓ Don't wait for long-term test—act on short-term results
4-10 pCi/L: Mitigation Strongly Recommended
Living at 4 pCi/L gives you roughly the same lung cancer risk as smoking half a pack of cigarettes per day. At 10 pCi/L, it's equivalent to a full pack per day.
✓ Confirm with second test (run another short-term test) ✓ If both show 4+ pCi/L, schedule mitigation within 2-4 weeks ✓ Get 2-3 quotes to compare pricing and warranties ✓ Most systems reduce levels to under 2 pCi/L
2-4 pCi/L: Consider Mitigation (Especially If...)
The World Health Organization recommends action at 2.7 pCi/L. The EPA chose 4 pCi/L as the action level because it's where mitigation becomes cost-effective—but there's no "safe" level of radon.
Consider mitigation if: ✓ You have young children (longer lifetime exposure) ✓ Anyone in household smokes (radon + smoking = 10x lung cancer risk) ✓ You plan to live in home long-term (10+ years) ✓ Someone has respiratory issues or weakened immune system ✓ You're pregnant or planning pregnancy
Budget option: Many contractors will install a passive system (pipe only, no fan) for $500-800. You can add a fan later if needed. This is popular for 2-4 pCi/L levels.
Under 2 pCi/L: Mitigation Not Necessary
Levels below 2 pCi/L are close to outdoor ambient levels (0.4 pCi/L average). Mitigation isn't cost-effective at these levels.
✓ Retest every 2 years (levels can change over time) ✓ Retest after major renovations or foundation work ✓ Consider continuous monitoring if you want peace of mind ✓ No action needed unless levels increase
What If My First Test Showed High But Second Test Showed Low?
If your first test showed 6 pCi/L but your second test shows 3 pCi/L, this indicates your home experiences variable radon levels. The EPA recommends using the higher result for decision-making, or running a long-term test (90+ days) to get the annual average.
Why the higher result matters: If radon spiked to 6 pCi/L once, it can spike again. Seasonal variations (winter vs summer), weather changes, and HVAC use all affect radon levels. Mitigation protects you during those high-radon periods.
How to Choose a Radon Mitigation Contractor
Radon mitigation is a specialized field. Not all general contractors or handymen can properly install systems. Here's what to look for:
Essential Qualifications:
State Certification or License
Every state requires radon contractors to be certified. Ask for their license number and verify it on your state's radon website. Unlicensed contractors cannot legally perform mitigation work and their systems won't be up to code.
NRPP or NRSB Certification
The National Radon Proficiency Program (NRPP) and National Radon Safety Board (NRSB) are the two national certification bodies. Look for contractors certified by either organization—this ensures they follow EPA protocols and best practices.
Written Warranty (Minimum 5 Years)
A good contractor guarantees their work. Most offer 5-10 year warranties covering system performance (i.e., "we guarantee levels will drop below 4 pCi/L"). If levels don't drop, they troubleshoot and fix it for free. Get this in writing.
Post-Mitigation Testing Included
The EPA requires post-mitigation testing to verify the system works. Many contractors include this in their quote (either a short-term test or continuous monitor reading). If not included, budget an extra $20-150 for testing.
Insurance and Bonding
Verify the contractor carries general liability insurance and is bonded. This protects you if they damage your home during installation (drilling through pipes, cracking foundation, etc.). Ask for proof of insurance before work begins.
Questions to Ask During Quotes:
- •"What's included in this quote?" (labor, materials, post-test, warranty)
- •"How many suction points will my home need?" (get specific reasoning)
- •"Where will the pipe be routed?" (exterior, interior, garage?)
- •"What radon level can I expect after mitigation?" (target: under 2 pCi/L)
- •"How long will installation take?" (usually 3-6 hours for standard systems)
- •"What's the warranty?" (5+ years minimum, get it in writing)
- •"What's the annual operating cost?" (fan electricity: $50-150/year)
- •"Do you offer financing or payment plans?" (some do for $1,500+ jobs)
⚠️ Red Flags (Walk Away If You See These):
- ❌Won't provide license/certification number
- ❌Promises to install system same day without assessing your home
- ❌Quote is 50%+ cheaper than other bids (cutting corners somewhere)
- ❌No written warranty or refuses to guarantee radon reduction
- ❌Pressure tactics ("prices go up tomorrow", "limited time offer")
- ❌Can't explain where suction points will go or why
Does Radon Mitigation Affect Home Value?
Short answer: Radon mitigation increases home value, especially in high-radon areas. Here's why:
✓ Mitigation is a Selling Point, Not a Red Flag
It Shows Proactive Maintenance
A properly installed mitigation system tells buyers: "This homeowner took radon seriously and solved the problem." It's proof the issue is addressed, documented, and warranted.
It Eliminates Buyer Concerns
In Zone 1 areas (high radon), buyers EXPECT to find elevated radon. A home with mitigation already installed is more attractive than a home where the buyer has to negotiate mitigation costs or walk away from the deal.
It Can Speed Up Closing
When radon is discovered during a home inspection, it can delay closing by 2-4 weeks while mitigation is installed. A home with an existing system avoids this delay entirely.
It May Increase Appraisal Value
Some appraisers in high-radon markets add $1,500-3,000 to home value for professionally installed mitigation systems, viewing it as a permanent home improvement similar to a new roof or HVAC system.
Real Estate Example: Denver Market
Denver is EPA Zone 1 with average radon levels of 6.2 pCi/L. In the Denver metro area:
- •67% of homes test above 4 pCi/L - Buyers expect radon issues
- •Homes with existing mitigation sell 5-10% faster - No inspection delays
- •Mitigation adds $2,000-4,000 perceived value - According to local realtors
- •Homes without mitigation often face $1,500 price reduction - Buyer demands seller pays for system or reduces price
Bottom line in Denver: Installing a $1,800 mitigation system before listing can increase sale price by $2,000-4,000 and reduce days on market by 10-15 days. It's a net positive ROI.
What About Low-Radon Areas (Zone 3)?
In Zone 3 areas where radon is uncommon (Houston, Miami, Dallas), mitigation systems are less common and may not add the same perceived value. However:
- • Systems still don't hurt value (buyers don't view them negatively)
- • Health-conscious buyers appreciate proactive safety measures
- • If your home tested high, buyers would discover it anyway during inspection
Even in low-radon areas, mitigation is neutral-to-positive for home value. It's never a dealbreaker.
What to Expect During Installation
Radon mitigation installation is a same-day job for most homes. Here's what happens:
Pre-Installation Assessment (15-30 minutes)
Contractor walks your home to determine:
- • Optimal suction point location(s)
- • Best pipe routing path (interior vs exterior)
- • Fan mounting location (attic vs exterior)
- • Any obstacles (plumbing, electrical, structural)
Drilling and Pipe Installation (2-4 hours)
The messy part:
- • Core drill through basement floor (4-6 inch hole) - LOUD but only takes 5-10 minutes
- • Vacuum out loose soil from beneath slab
- • Install PVC pipe from suction point to roofline
- • Seal pipe penetrations through floor and roof
- • Mount fan (attic or exterior wall)
- • Wire fan to dedicated electrical circuit
Expect: Some concrete dust (contractor should lay tarps), drilling noise for 5-10 minutes, and contractor walking through your home to route pipes.
Testing and Cleanup (30-60 minutes)
- • Install U-tube manometer (pressure gauge) in basement
- • Turn on fan and verify suction
- • Clean up debris, remove tarps
- • Walk you through system operation and monitoring
- • Provide warranty documentation and maintenance guide
Do I Need to Leave During Installation?
No. Most homeowners stay home during installation. The loud drilling only lasts 5-10 minutes total. You'll want to keep pets in a separate room away from the work area, but you don't need to vacate. The system is operational as soon as the fan is turned on—no curing time or waiting period.
Post-Installation Checklist:
- ✓Wait 24-48 hours before testing (gives system time to stabilize)
- ✓Run post-mitigation test to verify levels dropped (EPA requirement)
- ✓Check U-tube gauge monthly to ensure fan is running
- ✓Test annually to monitor system performance
- ✓Keep warranty paperwork for future reference or home sale
Testing After Mitigation
Post-mitigation testing is required by the EPA to verify your system is working effectively. Most systems drop radon levels by 90-99%, but testing confirms this.
When and How to Test:
⏱️ Wait 24-48 Hours After Installation
Give the system time to stabilize pressure under your foundation. Testing immediately after installation may not give accurate results. Most contractors recommend waiting 24 hours minimum.
🧪 Use a Short-Term Test (2-7 Days)
You don't need a long-term test for post-mitigation verification. A short-term test (48-96 hours) will show if the system is working effectively. Place the test in the same location you tested before mitigation (usually basement) for apples-to-apples comparison.
🎯 Target Level: Under 2 pCi/L
Most mitigation systems drop radon to 0.5-2 pCi/L. If your post-test shows:
- • Under 2 pCi/L: Excellent, system is working perfectly
- • 2-4 pCi/L: System is working but could be optimized (contact contractor)
- • 4+ pCi/L: System needs troubleshooting (should be covered under warranty)
Recommended Post-Mitigation Test Kits:
First Alert RD1 Short-Term Test
Quick verification test • ~$19
- ✓ 2-4 day test gives fast results
- ✓ EPA-approved for post-mitigation testing
- ✓ Lab fees included
- ✓ Same test most contractors use
Buy on Amazon →
Continuous monitoring option: If you want ongoing peace of mind, consider a digital radon monitor like the Airthings Wave Plus ($180). It provides real-time readings and alerts you if radon levels increase, which can happen if your fan fails or needs maintenance.
What If Post-Test Still Shows High Radon?
If levels are still above 4 pCi/L after mitigation, call your contractor immediately. Reputable contractors warranty their work--they'll troubleshoot and fix it for free. Common issues:
- • Suction point is in wrong location (need to drill additional hole)
- • Fan isn't powerful enough (need larger CFM fan)
- • Air leaks in system (joints not sealed properly)
- • Foundation cracks allowing radon bypass (need sealing)
A good contractor will diagnose and fix this within 1-2 days at no additional cost. If they push back or ask for more money, reference your warranty and demand they honor it.
Common Questions About Radon Mitigation
How long does a radon mitigation system last?
Radon fans are rated for 10-15 years of continuous operation. The PVC piping lasts indefinitely. Most homeowners replace the fan once after 10-15 years ($200-400) but the rest of the system requires no maintenance. Some fans last 20+ years if properly maintained.
Will my system make noise?
The fan produces a low hum similar to a refrigerator running. If installed in the attic or outside, you typically won't hear it. If installed in a garage, you'll hear a soft whirring sound. It's not loud—most people forget it's even running after a week.
Can I turn off the system when I'm not home?
No. The fan must run 24/7 to maintain negative pressure under your foundation. Turning it off allows radon to accumulate again. The electricity cost ($50-150/year) is minimal compared to the health risk of intermittent protection. Set it and forget it.
What if I finish my basement after mitigation?
Finishing a basement after mitigation is fine, but you'll need to retest afterward. Sealing the basement (drywall, flooring, ceiling) can change air pressure dynamics and potentially trap more radon. Your existing system may need adjustment (stronger fan or additional suction point). Always retest after major basement renovations.
Do I need to disclose mitigation when selling?
Disclosure requirements vary by state. Most states require sellers to disclose known radon issues, including the presence of a mitigation system. However, having a system installed is a POSITIVE—it shows you solved the problem. Provide buyers with your pre-mitigation test results, post-mitigation results, and warranty documentation. This transparency builds trust.
Can mitigation systems freeze in winter?
Properly installed systems won't freeze. The fan generates heat during operation, and the constant airflow prevents ice buildup. In extreme cold climates (Minnesota, North Dakota), contractors may insulate pipes or install heat tape as a precaution. If you're in a cold climate, ask your contractor about winterization measures.
What happens if my fan fails?
You'll know immediately. The U-tube manometer (pressure gauge) will show zero pressure differential, indicating the fan isn't running. Radon levels will gradually increase back to pre-mitigation levels over 1-2 weeks. If your fan fails, call your contractor for replacement (should be covered under warranty if within warranty period). Don't ignore a failed fan—replace it within a few days.
Ready to Fix Your Radon Problem?
Don't let high radon levels threaten your family's health. Professional mitigation systems work—they reduce radon by 90-99% and last 10-15+ years with minimal maintenance.
Average response time: 24-48 hours • NRPP-certified contractors • No obligation quotes