Aluminum Fell Thirteen Points In A Month While Steel Kept Climbing

Aluminum mill shapes rose 27.3% over twelve months in August, against 40.5% in July — a 13.2-point deceleration in a single month. Month over month, aluminum fell 4.4%, following a 1.6% July decline. Two consecutive drops, the second nearly triple the first. BLS named aluminum a decliner three separate times in the August summary and published no rate. This is that rate.

Nothing else in the metals block moved with it. Steel mill products rose 1.7% on the month and stand at +23.4% for the year. Copper and brass mill shapes rose 3.5%, at +20.9%. Primary nonferrous metals sit at +49.3% and rose again. Secondary nonferrous is at +36.6% and rose. Nonferrous wire and cable is at +19.6% and rose. Iron and steel scrap eased 0.7% to +9.5%.

The base matters as much as the move. Aluminum entered August at +40.5% — one of the steepest twelve-month rates in the whole index. A 13.2-point retreat off that base is not a normalization toward the mean; it is a single line detaching from a complex that is otherwise still accelerating.

The rest of the construction bill did not cooperate with any simple story either. Cement is in outright deflation at -1.2% year over year. Softwood lumber is +11.8% for the year but fell 2.9% in August, reversing a +8.2% July. Fabricated structural metal is +6.5%. Switchgear and industrial controls are +12.3%, transformers +7.6%, electronic components +27.6%. New warehouse building construction is +4.3% for the year; final demand construction +5.3%. No. 2 diesel is +77.8% year over year.

ABC's derived series puts construction input prices at +1.2% on the month and +8.9% year over year, with nonresidential at +1.2% and +8.8%.

What emerges is not an inflation curve but a dispersion problem. Trades whose cost is concentrated in aluminum — curtain wall, storefront, some roofing and framing systems — just got relief that trades concentrated in copper, steel or electrical gear did not. Two buildings with the same gross budget can now diverge materially on the strength of their envelope specification alone.

Implications

Blanket escalation contingencies priced off a single composite index are now mispricing risk in both directions. The useful move is line-item exposure analysis — what share of this budget is aluminum, what share is copper and switchgear — and buyout sequencing timed to the divergence. Projects heavy in electrical distribution should assume the pressure continues; projects heavy in aluminum envelope have a window.

Flags: all August figures are preliminary. The ABC construction-input series is ABC's own weighted construct, not a BLS-published series.