Producer Price Index for insulation materials, a WPU13 nonmetallic mineral products series. Its published sub-series are mineral wool for thermal and acoustical envelope insulation and mineral wool for industrial, equipment and appliance insulation.
Paste straight into Excel, Google Sheets or an email. Spreadsheet format lands as two columns.
| Month | Value | Change m/m |
|---|---|---|
| Sep 2026 | +1.6% | |
| Aug 2026 | +0.5% | |
| Jul 2026 | −0.5% | |
| Jun 2026 | −0.1% | |
| May 2026 | +0.5% | |
| Apr 2026 | −0.7% | |
| Mar 2026 | +0.7% | |
| Feb 2026 | +0.6% | |
| Jan 2026 | −0.1% | |
| Dec 2025 | +0.6% | |
| Nov 2025 | +0.5% | |
| Oct 2025 | −0.8% | |
| Sep 2025 | −0.1% |
Same numbers as the chart, straight from BLS. Dates are the first of each period, the way BLS reports them.
Insulation materials rose 2.7% over the last 12 months, but 1 of its main inputs rose faster: industrial electric power +4.2%. That cost pressure may still pass through to prices.
Nonmetallic mineral productsOther nonmetallic minerals
A starting point citing this series by name and code. Replace the bracketed terms with your contract's actual scope before use.
The [affected portion] of the Contract Price shall be adjusted using US PPI — Insulation Materials (BLS series WPU1392), published by BLS. Base Period: the index value published for September 2026 (or the month of contract signing, if different) is the Base Value. Adjustment: at each Adjustment Date, the Current Value is the most recently published three-month average of the index (the Averaging Window). The Escalation Factor equals Current Value divided by Base Value. Cap: the Escalation Factor applied under this clause shall not exceed 1.10 or fall below 0.90 (a 10% cap and floor) in any single Adjustment Date, regardless of the index's actual movement. [Replace bracketed terms with your contract's actual affected-portion definition and adjustment-date schedule before use. This is a drafting starting point, not legal advice.]
Building envelope and mechanical insulation subcontracts name this series as a general insulation escalator. Its published sub-series are mineral wool, so a contract that buys another insulation type should check the fit.
Divide the current value of BLS series WPU1392 (Insulation Materials) by its value at contract signing, then apply that ratio to the mineral wool insulation part of the price. A usable clause also names an averaging window, a rule for revised values and missing months, and a cap.
Escalake tracks US PPI — Insulation Materials, applies your formula, and gives both sides a number they can confirm, no spreadsheet required.