Crawl Space Service Areas
19 cities in King and south Snohomish counties, listed here by county because that is what a permit desk and a health department follow. Washington registers construction contractors through the Department of Labor & Industries; check any contractor’s registration before you sign.
Each city page covers what its own measured figures say about the ground and the housing: when the houses were built according to the Census, how much of the city the USDA soil survey rates as poorly drained, and who issues the permits. The one-line notes below are computed from the same climate and housing dataset, so they rank each city against the 19 in it. Where most of a city is mapped as Urban land with no drainage class (Burien, Shoreline and Seattle), its soil figure is not ranked, because a near-zero poorly drained share there means the ground was not rated, not that it drains well.
None of that diagnoses a particular house. If you do not yet know what is wrong under yours, what a crawl space inspection covers explains how a contractor’s visit gets from a symptom to one written scope, and what to ask before accepting it. For what to check before you hire, see crawl space repair in Seattle: how to choose a contractor.
King County
Seattle, the Eastside cities of Bellevue, Kirkland, Redmond, Sammamish, Issaquah and Mercer Island, Shoreline, Kenmore and Bothell to the north, and Renton, Kent, Federal Way, Auburn, Burien and Des Moines to the south. Bothell also extends into Snohomish County and Auburn into Pierce County. Electrical permits split by city: Seattle, Bellevue, Kirkland, Redmond, Sammamish, Mercer Island, Renton, Federal Way, Burien and Des Moines issue their own, while in Issaquah, Shoreline, Kenmore, Bothell, Kent and Auburn they come from Washington L&I. Inside Seattle, plumbing permits come from Public Health — Seattle & King County. The EPA places King County in radon Zone 3, its lowest category.
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Seattle
30.1% of homes built before 1950, the highest share measured; 87.1% of mapped ground has no soil drainage class.
ZIPs: 98101, 98102, 98103, 98104...
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Bellevue
Median home built in 1982; 6.5% of mapped ground rated poorly drained.
ZIPs: 98004, 98005, 98006, 98007...
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Kirkland
Median home built in 1984; 3.1% of mapped ground rated poorly drained.
ZIPs: 98033, 98034
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Redmond
Median home built in 1993, the third-newest median measured; 13.6% of mapped ground rated poorly drained.
ZIPs: 98052, 98053
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Sammamish
Median home built in 1994, the second-newest median measured; 3.5% of mapped ground rated poorly drained.
ZIPs: 98029, 98074, 98075
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Issaquah
Median home built in 2002, the newest median measured; 19.7% of mapped ground rated poorly drained.
ZIPs: 98027, 98029
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Mercer Island
Only 0.7% of mapped ground rated poorly drained, the lowest share measured; median home built in 1973.
ZIPs: 98040
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Shoreline
65.2% of homes built before 1980, the second-highest share measured; 82.3% of mapped ground has no soil drainage class.
ZIPs: 98133, 98155, 98177
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Kenmore
Median home built in 1985; 6.4% of mapped ground rated poorly drained.
ZIPs: 98028
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Bothell
Median home built in 1992; 16.7% of mapped ground rated poorly drained. Also extends into Snohomish County.
ZIPs: 98011, 98021
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Renton
Median home built in 1988; 9.7% of mapped ground rated poorly drained.
ZIPs: 98055, 98056, 98057, 98058...
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Kent
19.2% of mapped ground rated poorly drained, the third-highest share measured; median home built in 1985.
ZIPs: 98030, 98031, 98032, 98042
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Federal Way
Median home built in 1984; 4.1% of mapped ground rated poorly drained.
ZIPs: 98001, 98003, 98023
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Auburn
23.4% of mapped ground rated poorly drained, the highest share measured; median home built in 1991. Also extends into Pierce County.
ZIPs: 98001, 98002, 98092
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Burien
67.1% of homes built before 1980, the highest share measured; 82.4% of mapped ground has no soil drainage class.
ZIPs: 98146, 98148, 98166, 98168
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Des Moines
Only 0.9% of mapped ground rated poorly drained, the second-lowest share measured; median home built in 1974.
ZIPs: 98148, 98198
Snohomish County
Lynnwood, Edmonds and Everett, the southern part of the county. Lynnwood and Everett issue their own electrical permits; in Edmonds they come from Washington L&I. Like King County, Snohomish County is in the EPA’s radon Zone 3. Coverage stops at Everett: the county north of it is outside the service area.
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Lynnwood
Median home built in 1979; 8.9% of mapped ground rated poorly drained.
ZIPs: 98036, 98037
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Edmonds
Only 1.9% of mapped ground rated poorly drained, the third-lowest share measured; median home built in 1974.
ZIPs: 98020, 98026
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Everett
20.1% of homes built before 1950, the third-highest share measured; 10.3% of mapped ground rated poorly drained.
ZIPs: 98201, 98203, 98204, 98207...
Service Area FAQs
- Seattle Crawlspace Pros accepts free inspection requests from 19 places in King and south Snohomish counties: Seattle; Bellevue, Kirkland, Redmond, Sammamish, Issaquah and Mercer Island; Shoreline, Kenmore and Bothell; Lynnwood, Edmonds and Everett; and Renton, Kent, Federal Way, Auburn, Burien and Des Moines. Tacoma and the rest of Pierce County, Kitsap County, Snohomish County north of Everett and the area east of Issaquah and Sammamish are not covered. Enter your ZIP code in the free inspection form and it confirms coverage before you fill in anything else.
- The county. In unincorporated King County building permits come from the county's Permitting Division, which lists the work that needs no permit, and crawl space work is not on that list. In unincorporated Snohomish County the office is Planning and Development Services. Inside a city, the city's own permit desk applies, and the city pages say which one. Whoever does the work, it is worth confirming in writing which office they are pulling permits from.
- Washington registers construction contractors through the Department of Labor & Industries (L&I), and every contractor must register: it is a gross misdemeanor to bid or work as a contractor while unregistered. Registration requires a bond and liability insurance. Electrical and plumbing work carry their own licensing on top. Look up any contractor's registration, bond and insurance on L&I's Verify a Contractor tool before you sign, and see how to read a Washington contractor record.
- Your ZIP confirms you are inside the 19-place service area and places you in one of five zones: Seattle, the Eastside, North King, Snohomish County and South King. ZIP codes do not follow city limits, so where one is shared between two places the form names the one that holds most of its land. Enter your ZIP in the free inspection form and it confirms your zone before you fill in anything else. If your ZIP is not recognized but you live in one of the 19 places, contact us and we will sort it out.
- The same thing in every city: what is wrong under this particular house and what would fix it. The city pages describe the ground and the housing around you, which is useful for reading a quote but cannot diagnose a single crawl space. What a crawl space inspection covers sets out what a contractor's pre-quote visit should establish, how it differs from a home inspection ordered during a sale, and the questions worth asking before a scope is priced.
- Not in the ranges this site publishes: every figure on the cost guide is a metro-wide modeled range before sales tax, and no city has one of its own. Two things do differ. Sales tax applies to the whole contract price at the rate for the job site, and across these cities that rate runs from 9.9% to 10.7% (10.55% in Seattle). And the job differs: on a sloping lot where water arrives from uphill, a curtain drain is quoted on top of an interior drainage scope at $2,250 to $5,375 more, while a house that has never had ground cover starts with that. The city pages say which pattern their measured figures point to.
Sources for the county and city notes
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United States Census Bureau, American Community Survey 5-Year Estimates — Year Structure Built (B25034) and Median Year Structure Built (B25035) (ACS 2020–2024 5-year estimates, tables ACSDT5Y2024.B25034 and ACSDT5Y2024.B25035) Open dataset
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USDA Natural Resources Conservation Service, Soil Survey Geographic Database (SSURGO), via Soil Data Access (muaggatt.drclassdcd — drainage class, dominant condition) Open dataset
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U.S. Census Bureau, 2020 ZIP Code Tabulation Area (ZCTA5) to 2020 Place Relationship File (tab20_zcta520_place20_natl.txt) Open dataset
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Washington State Department of Labor & Industries, City Electrical Permits & Inspections
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Public Health — Seattle & King County, Plumbing and gas piping: applications and permits
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U.S. Environmental Protection Agency, EPA Map of Radon Zones — Washington
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King County Department of Local Services, Permitting Division, Do you need a permit?
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Snohomish County, Planning and Development Services
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Washington State Legislature, RCW 18.27.020 — Registration required; prohibited acts; criminal penalty
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Washington State Department of Labor & Industries, Register as a Contractor
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Washington State Department of Labor & Industries, Verify a Contractor, Tradesperson or Business
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Washington State Legislature, RCW 82.04.050 — “Sale at retail,” “retail sale” (Subsection (2)(b))
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Washington Department of Revenue, Construction industry guide: Custom construction Explanatory summary, not the governing text
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Washington Department of Revenue, Local sales and use tax rate table (Quarter 4 2026, effective October 1 through December 31, 2026)
Sources last checked between and .
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