The September Producer Price Index (PPI) from the U.S. Bureau of Labor Statistics (BLS) was released this week, following a month-long delay caused by the government shutdown. The latest PPI shows prices for materials used in door and window manufacturing mostly continuing to increase across the board, not only from August to September 2025, but on a year-over-year basis.
In September, the monthly PPI for flat glass in the commodity category continued to climb, rising by 0.1% from the previous month and up 4% compared to the previous year. Also classified as a commodity, the prices for softwood lumber dropped 3.4% from August 2025, translating to a 1.4% decrease from September 2024 as well. According to BLS, the commodity classification “organizes products and services by similarity or material composition, regardless of the industry classification of the producing establishment.”
The index for flat glass manufacturing in the industry classification flat-lined from August 2025 while registering a 4.4% increase on a year-over-year basis. The industry classification measures “changes in prices received for the industry’s output sold outside the industry (that is, its net output).”
The PPI for metal windows increased by 0.9% from August, registering at 7.8% over the September 2024 report. Prices for metal doors and frames also increased from August to September, climbing 0.1%, notching an 11.8% rise since last year. Prices for wood window units rose 0.1% from the previous month, up 5.4% on a year-over-year basis. Prices for wood doors for interior and exterior applications showed a decrease in prices for September 2025, slipping 0.4% from August, which carried over to a 4.4% drop from September 2024 pricing.
The price for thermoplastic resins and plastic materials showed no change compared to August 2025, while dropping 1.6% from September of last year. Prices for fiberglass plastic products also stagnated from the previous month while showing an increase of 1.8% over the previous September.
The cost of builders’ hardware, which includes hardware used in doors and windows, rounded out the readings with no change from August to September, but rose by 8.8% from September 2024.
Monthly and Yearly Change in Door and Window Material Prices
| Category | August to September 2025 | September 2024 to September 2025 |
| Flat Glass | +0.1% | +4.0% |
| Softwood Lumber | -3.4% | -1.4% |
| Flat Glass Manufacturing | 0.0% | +4.4% |
| Metal Windows | +0.9% | +7.8% |
| Metal Doors and Frames | +0.1% | +11.8% |
| Wood Window Units | +0.1% | +5.4% |
| Wood Doors | -0.4% | -4.4% |
| Thermoplastic Resins and Plastic Materials | 0.0% | -1.6% |
| Fiberglass Plastic Products | 0.0% | +1.8% |
| Builders’ Hardware | 0.0% | +8.8% |