Vashon, WA Radon Mitigation and Testing

Q: What EPA Radon Zone is Vashon in?

Vashon is in King County, EPA Zone 3.

Q: How much does radon mitigation cost in Vashon?

Radon mitigation typically costs between $800 and $2,000. Most standard systems fall in the $1,000-$1,500 range.

King County

EPA Zone 3

This island community in King County sits on glacial deposits and marine sediments in Puget Sound, creating unique geological conditions within the Seattle Metro area. Radon testing data for zip code 98070 is currently limited, making island-specific conditions difficult to assess. Given the area's mix of older homes and varied foundation types, Vashon residents should conduct individual testing to understand their radon exposure levels.

Vashon, WA Radon Mitigation

Professional radon mitigation is the most effective way to permanently lower radon levels and protect your household.

Vashon, WA Radon Testing

Finding qualified radon testing professionals is the first step toward protecting your home.

Vashon Radon Facts

Key details about the radon risk profile for Vashon and the 98070 zip code area.

EPA Radon Zone

Zone 3 — Low Risk

County

King County, WA

Zip Code

98070

Predicted Screening Level

< 2.0 pCi/L (Zone 3)

Vashon and the 98070 zip code are located in King County, which has an EPA assigned Radon Zone of 3. A radon zone of 3 predicts an average indoor radon screening level less than 2 pCi/L. The EPA recommends testing every home regardless of zone classification.

Radon FAQ for Vashon, WA

What EPA Radon Zone is Vashon in?

Vashon and the 98070 zip code are in King County, which has an EPA assigned Radon Zone of 3. A zone of 3 predicts an average indoor radon screening level less than 2 pCi/L.

How much does radon mitigation cost in Vashon?

Radon mitigation in Vashon 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 Vashon?

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 Washington

Cities with the most user-submitted radon test data in the state.

City	Avg User Radon Level	Submissions
Vancouver	6.56 pCi/L	9
Kent	3.60 pCi/L	5
Seattle	5.25 pCi/L	4
Olympia	5.00 pCi/L	4
Bellevue	3.75 pCi/L	4
Spokane	11.67 pCi/L	3
Camas	8.00 pCi/L	3
Centralia	7.00 pCi/L	3
Bellingham	4.50 pCi/L	2
Kirkland	4.50 pCi/L	2
Washougal	8.00 pCi/L	1
Ridgefield	5.00 pCi/L	1
Moses Lake	No submissions	0