Seattle & PNW Building Costs — 2026-May: Copper & Brass Mill Shapes Leads the Climb (+33.55% YoY)
What it really costs to build in King, Pierce & Snohomish right now — materials, labor, codes and storm risk, from primary sources.
Materials: 4 of 5 tracked categories are up year-over-year
The biggest mover is Copper & Brass Mill Shapes, up 33.55% year-over-year (+14.32% in the last month) as of 2026-May. Producer Price Index (BLS).
| Material | Index | YoY | MoM |
|---|---|---|---|
| Copper & Brass Mill Shapes | 452.405 | +33.55% | +14.32% |
| Steel Mill Products | 423.758 | +9.97% | +1.15% |
| Lumber & Wood Products | 280.994 | +4.19% | +0.29% |
| Concrete Products | 404.645 | +3% | +0.28% |
| Gypsum Products | 353.707 | -1.19% | +1.76% |
What it means for your project: when a category is climbing, locking material orders early on a signed scope protects your budget. We bake the current trend into every Prolific estimate.
Labor: PNW construction wages
- King County: ~$64.28/hr all-in average (+6.8% YoY)
- Pierce County: ~$46.05/hr all-in average (-4.2% YoY)
- Snohomish County: ~$46.58/hr all-in average (+6.4% YoY)
What this number is — and isn't: these are BLS averages across all construction roles in each county — a market gauge, not a quote for your project and not a single-trade journeyman rate. Your actual labor cost depends on scope, trade mix, and complexity. We use these as one input, then price your specific job.
Codes: WA 2024 code adoption DELAYED — effective date now May 3, 2027
The WA State Building Code Council voted Jan 2026 to delay the 2024 Washington State Building Codes: final adoption targeted Aug 21-28, 2026 with an effective date of May 3, 2027 (CR-102 filed for IBC/IRC/IMC/IFC/UPC; public comment May 6-June 12, 2026). Takeaway: nothing changes on the ground until May 2027 - plan and permit to the 2021 I-Codes through then; budget for 2024-code upgrades on projects breaking ground after spring 2027. Verified 2026-06-17.
Methodology
Materials = BLS Producer Price Index. Labor = BLS QCEW. Codes = WA State Building Code Council. Storm = NOAA NWS. Prolific distills these public signals with AI cost models and our own completed-job history into a consensus range.
Building, remodeling, or recovering from damage in King, Pierce, or Snohomish County? Get a free, data-backed estimate →