Typical low · P25$12,000
Median$30,000
Typical high · P75$100,000
✓ Verified from 1,934 recent building-permit filings in Seattle, WA
Data refreshed July 2026
Computed from 1,934 recent building-permit filings in Seattle, WA — what people actually declared, not survey guesses.
✓ Verified from 1,934 recent building-permit filings in Seattle, WA
Data refreshed July 2026
The short answer: a typical deck / decking build in Seattle costs around $30,000, with half of all projects landing between $12,000 and $100,000. If a quote falls well outside that range, it isn't automatically wrong — but it deserves an explanation you can understand.
Every figure on this page is computed from declared valuations on building permits published by Seattle's open-data portal. We report the 25th percentile, median and 75th percentile of 1,934 recent residential filings — never a single-point "average". Declared values are what applicants file, not final invoices, so treat the range as planning guidance rather than a quote. Full methodology →
Based on 1,934 recent building-permit filings in Seattle, the median declared cost is $30,000. Half of all projects fall between $12,000 and $100,000.
No. Permit valuations are what applicants declare when filing, not final invoices. Treat the range as planning guidance and a sanity-check against the quotes you receive.
Because identical-sounding projects legitimately differ in size, specification and site conditions. That is why we publish the 25th percentile, median and 75th percentile instead of a single misleading "average" — you can see where a quote sits in the real distribution.
Planning something else, or somewhere else? Request a city or project — requests decide what we ingest next.