Portola Valley, CA Radon Levels
Check local Portola Valley radon levels and find certified testing and mitigation professionals to keep your home safe
Portola Valley, CA Radon Facts
EPA Radon Zone
Zone 2 — Moderate Risk
2–4 pCi/L (Zone 2)
County
San Mateo County, CA
Zip Code
94028
Tucked into the hills of San Mateo County in the San Francisco Bay Area, this upscale community sits on sedimentary rock formations and alluvial soils. Testing data for zip code 94028 remains limited, but the area's geological diversity and custom homes built into hillsides warrant professional radon evaluation. Many properties feature unique foundation configurations due to the sloped terrain.
Portola Valley, CA Radon Mitigation
Professional radon mitigation is the most effective way to permanently lower radon levels and protect your household.
Need Radon Mitigation or Testing in Portola Valley?
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Radon FAQ for Portola Valley, CA
What EPA Radon Zone is Portola Valley in?
Portola Valley and the 94028 zip code are in San Mateo County, which has an EPA assigned Radon Zone of 2. A zone of 2 predicts an average indoor radon screening level between 2 and 4 pCi/L.
How much does radon mitigation cost in Portola Valley?
Radon mitigation in Portola Valley typically costs between $800 and $2,000. Most homes with standard basements can be mitigated with a sub-slab depressurization system in the $1,000–$1,500 range. Factors that can increase cost include complex foundations, crawl spaces, or very high radon levels.
Should I test for radon if I'm buying a home in Portola Valley?
Yes. Radon testing should be part of every home purchase. A short-term radon test is typically included as part of the home inspection process and costs $150–$250. If elevated levels are found, you can negotiate mitigation as part of the sale.
Most Active Radon Markets in California
Cities in California with the most user-submitted radon test data, ranked by number of submissions.
| City | Avg User Radon Level | Submissions |
|---|---|---|
| Los Angeles | 7.83 pCi/L | 6 |
| Mammoth Lakes | 10.80 pCi/L | 5 |
| San Jose | 4.20 pCi/L | 5 |
| Rancho Palos Verdes | 8.00 pCi/L | 4 |
| Bishop | 6.25 pCi/L | 4 |
| Oakland | 5.00 pCi/L | 4 |
| Woodland Hills | 7.67 pCi/L | 3 |
| South Lake Tahoe | 6.33 pCi/L | 3 |
| Palos Verdes Peninsula | 6.00 pCi/L | 3 |
| Sacramento | 4.33 pCi/L | 3 |