Metal Windows Price Trends: BLS PPI Checklist for Bidders
Estimating commercial assemblies that incorporate aluminum and steel windows requires tracking commodity cost shifts carefully. When pricing exterior wall packages or coordinating rough openings alongside a metal stud framing takeoff, subcontractors cannot rely on outdated historical budgets. Metal window prices have climbed significantly over recent years, making index-based bid validation essential.
Checklist Step 1: Audit Window Quotes Against Series WPU107103
The primary benchmark for factory-fabricated metal window units is the BLS Producer Price Index series WPU107103, titled "Metals and metal products-Metal windows (except storm sash), not seasonally adjusted." This metric tracks wholesale price changes using a base period where June 1983 equals 100.
As of September 2026, the index sits at 487.1 (raw value 487.074). One year earlier, in September 2025, the index stood at 437.7 (raw value 437.739). That shift represents an 11.3% increase in a single 12-month span. Estimators reviewing supplier quotes should verify whether local distributor adjustments align with or exceed this broader manufacturing trend.
Checklist Step 2: Measure Multi-Year Escalation Since 2020
Longer-duration project schedules require an understanding of how compound price growth has affected window packages over a multi-year horizon. Metal window indices experienced sustained upward pressure over the past several years:
- Two-year movement: In September 2024, the index was 406.0, indicating a 20.0% increase to the September 2026 level of 487.1.
- Five-year movement: In September 2021, the index registered at 312.9, reflecting a 55.7% rise to latest levels.
- Pre-pandemic comparison: In January 2020, the index recorded a reading of 266.3. The latest figure of 487.1 marks an 82.9% surge above that pre-pandemic marker.
Looking at annual averages illustrates the shift: the series averaged 263.8 in 2019, 272.0 in 2020, 306.9 in 2021, 391.0 in 2022, 405.0 in 2023, 404.5 in 2024, and 428.3 in 2025. Across January through September 2026, the average stands at 482.3.
Checklist Step 3: Analyze Recent Monthly Plateau Patterns
While the long-term trend has shown steep escalation, recent monthly readings point to short-term stability. The series hit a peak of 487.1 in July 2026, which represents the highest monthly value recorded between January 2019 and September 2026. The lowest level across that entire window occurred in January 2019 at 259.6.
Over the last 13 consecutive months, monthly values moved from 437.7 in September 2025 up through 448.5 in October, 474.2 in November and December 2025, to 475.7 in January 2026. The index recorded 476.2 in February and March 2026, climbed to 481.2 in April, 484.6 in May, and 485.4 in June. Since hitting 487.1 in July 2026, the index held flat through August 2026 (487.1) and September 2026 (487.1), showing a month-over-month change of 0.0% and sitting at 0.0% versus its peak.
Historical Metal Window Benchmark Figures
Below is a summary of benchmark price levels reported in the U.S. Bureau of Labor Statistics commodity data for metal windows:
| Time Period | Index Value | Change to Latest (September 2026) |
|---|---|---|
| Latest Value (September 2026) | 487.1 | 0.0% |
| One Year Earlier (September 2025) | 437.7 | +11.3% |
| Five Years Earlier (September 2021) | 312.9 | +55.7% |
| Pre-Pandemic Benchmark (January 2020) | 266.3 | +82.9% |
| Window High (July 2026) | 487.1 | 0.0% |
Checklist Step 4: Protect Metal Window Bids During Contract Setup
Because metal window pricing experienced an 11.3% increase in just one year, carrying fixed quotes on extended build schedules introduces substantial risk. Estimators should structure their proposals with clear material safeguards:
- Confirm the exact date and duration limit of all subcontractor and manufacturer quotes.
- Incorporate structured price escalation clauses tied to recognized commodity metrics for long-lead procurement.
- Account for the fact that the index base began at June 1983 = 100 when establishing formula multipliers.
Checklist Step 5: Verify Preliminary Data Status
When incorporating recent BLS figures into formal bid adjustments, note that these numbers are not seasonally adjusted. Furthermore, monthly values from the most recent four months remain preliminary and subject to monthly revisions by the data agency. Always note the revision status when establishing baseline calculations.
Sources
U.S. Bureau of Labor Statistics, Producer Price Index series WPU107103
Published November 9, 2026. No affiliate links on this page. Facts come from the sources linked above; check them for updates.