§01
Why Allegheny County PA radon is expensive. And why $400 'fix kits' don't work
Allegheny County's geology. Underlying Marcellus shale + heavy glacial-till soil + variable bedrock fracturing. Produces some of the highest indoor radon levels in the United States. Pre-1980 homes without active sub-slab depressurization (ASD) routinely test in the 8-25 pCi/L range. Mitigation cost is driven by home characteristics (slab geometry, soil permeability, foundation type) and contractor experience. The $400 radon-fix products you'll see at big-box hardware stores (passive ventilation kits) are not effective at Zone 1 levels and are not accepted by FHA or conventional lenders for closing documentation.
§02
Active sub-slab depressurization (the standard for Allegheny)
Active sub-slab depressurization (ASD) is the appropriate mitigation system for nearly all Allegheny County homes. The system uses a continuous-running radon fan to create negative pressure beneath the basement slab, pulling radon-laden soil gas through a vent pipe to outside-discharge above the roof line. System components: 3-inch or 4-inch PVC vent pipe penetrating the basement slab, in-line radon fan (Radon-Away RP-145, RP-265, GP-301 are common Allegheny County selections sized to home footprint), manometer pressure gauge, exterior vent termination at roof line. Typical installation cost in Allegheny County 2026: $1,200-$2,800 depending on home size, basement layout, and fan sizing.
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What drives the price range
$1,200 ASD installs are typical for small ranch-style homes with simple basement layout + accessible slab penetration. $2,800 ASD installs are typical for larger 2-3 story homes with finished basement (requiring drywall + flooring restoration), multiple slab segments requiring tied-together suction points, or aesthetic concerns requiring concealed pipe routing. Two-suction-point systems (typical for 2,500+ sq ft homes) add $400-$700 over single-suction systems. Brick-veneer homes requiring exterior vent routing add $200-$400 for the routing work.
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What's NOT in the install price
Post-mitigation radon re-testing (recommended at 4-6 weeks post-install per EPA protocol) is typically billed separately at $150-$245 in Pittsburgh. This is the test that documents whether the mitigation system actually achieved the target reduction. Some Allegheny County mitigators include re-testing in their package price; many don't. Annual radon re-testing every 2-5 years is recommended after install, $150-$245 per test.
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Real cost examples (anonymized Allegheny County 2024-2025 projects)
1,400 sq ft Squirrel Hill ranch (1968 construction), single-suction ASD, exterior vent route: $1,485 install + $185 post-mitigation re-test. 2,800 sq ft North Hills 2-story (1985 construction), two-suction ASD with concealed routing through closet, finished basement: $2,640 install + $185 post-mitigation re-test. 3,200 sq ft Mt. Lebanon split-level (1976 construction), two-suction ASD plus rim-joist sealing: $2,820 install + $185 post-mitigation re-test.
