Building material prices, August 2026: lumber, concrete, steel, copper wire, gypsum and asphalt roofing

The table: nine producer price series for August 2026

Each row below is a BLS Producer Price Index series. The value is an index, not a dollar price: 100 is the price level in the base period (1982 for most rows), so a reading of 300 means producers get three times what they got then. What matters for a budget is the percent change, and those are in the last three columns.

P means preliminary. All nine series are not seasonally adjusted, so a one-month change can carry some seasonal pattern; the 12- and 24-month changes compare the same month and cancel it. The percent columns are computed on this page as (newer value / older value) minus 1, rounded to one decimal.

Three readings stand out. Copper wire hit 602.480, the highest value in the 32 months pulled for this guide, after a 4.2% jump in a single month. Steel mill products have risen every month since November 2025, from 291.6 to 381.2. Softwood lumber peaked at 300.547 in July, also the high of the window, and gave back 1.9% in August.

What a producer price index is, and what it is not

BLS defines the PPI as the average change over time in selling prices received by domestic producers. It is measured from the seller's side. The softwood lumber index tracks what sawmills get for lumber; the copper wire index tracks what wire makers get for wire and cable.

That has three consequences for anyone budgeting a job.

First, it is not the price at the lumber yard or the big-box store. BLS itself notes that seller and buyer prices differ because of taxes and distribution costs. Between the mill and your deck sit a wholesaler, a retailer, freight and sales tax, and each takes a margin that does not move one for one with the mill price.

Second, retail lags. A dealer sells from stock bought weeks or months earlier, so the August mill dip in lumber will not show on a shelf tag in August, and July's 6.4% jump may still be working its way through. The lag and the pass-through vary by product, region and dealer, and this guide does not assume a fixed number for either.

Third, the index is an average over many products and sellers. "Prepared asphalt and tar roofing and siding products" is a group that also contains roll roofing and cap sheets, and "copper wire and cable" is a group too. Your specific product can run ahead of or behind its group.

What the index is good for: it is published monthly on a fixed schedule, it covers the whole country, and it cannot be quietly edited by a supplier. That makes it the right yardstick for direction, for size of move and for contract clauses. It is the wrong tool for pricing an individual order.

What the moves do to three real projects

The method is simple and you can redo it with your own quote. Run each project through the site's calculator with its default US prices, split the materials bill into lines, match each line to the index that best describes it, and multiply the line by that index's 12-month change. A line with no good index match is held flat and labeled. The result answers one question: if this year's producer move reached your price in full, how many dollars would it add to this basket?

A 12 by 16 ft pressure-treated deck

Inputs to the deck cost calculator: 16 ft along the house, 12 ft out, 2 ft high, treated pine, 5.5 in boards with a 3/16 in gap, 16 ft boards, joists at 16 in on center, 10% waste, no railing (the deck is under the 30 in height that triggers one) and no stairs. Default prices: decking $6.04 per sq ft, joists $2.60 per ft, beams $4.20 per ft, posts $3.40 per ft, footings $38 each, fasteners $45 a box, labor $16 per sq ft.

The module counts 26 rows of decking, 13 joists (156 ft), 3 beam lines (48 ft), 12 posts at 2.98 ft each and 12 footings, with 2 boxes of screws. Materials come to $2,623.23, labor to $3,072.00, total $5,695.23.

$277.16 is 10.6% of the materials bill and 4.9% of the installed price. On the 24-month change the same basket gains $419.12. The steel line is a proxy: screws and hangers are finished steel goods, not mill products, so treat that $21 as a rough upper bound. The labor line does not move at all in this exercise, and in a deck it is the bigger half of the bill.

A 20 by 24 ft concrete driveway slab

Inputs to the concrete calculator: 24 by 20 ft, 4 in thick, 8% waste, 3,000 psi ready-mix at $175 per cubic yard, a 4 yd minimum load, a 10 yd truck and a $120 delivery fee. The module returns 5.93 cubic yards net and 6.40 yd to order, one truck, $1,120.00 of concrete plus $120.00 delivery, $1,240.00 in all.

Push the $1,120.00 concrete line by the 2.3% ready-mix move and it adds $25.59. The delivery fee is held flat. That is 2.1% of the $1,240 delivered bill, and it is smaller than the error from ordering half a yard too little and paying for a second truck.

Rebar is where the driveway's steel risk sits. The calculator does not price reinforcing, so here is the rate instead: every $1,000 of rebar and wire mesh in a bid from August 2025 corresponds to $1,236.45 at August 2026 producer prices, using the bar joists and reinforcing bars index (WPU1074051, +23.6%). Whatever that line is in your bid, it is the part of the driveway that moved this year.

A 2,000 sq ft architectural shingle roof

Inputs to the roofing calculator: a gable roof at 6/12 pitch with 2,000 sq ft of actual roof surface (a 1,789 sq ft footprint times the 6/12 pitch factor of 1.118), architectural shingles at $46 a bundle, 10% waste for a gable, synthetic underlayment at $115 a roll, ice and water shield at $145 a roll covering 60 ft of eave, ridge cap at $3.50 per ft, drip edge at $1.60 per ft, nails at $3 per square, labor at $250 per square, one layer of tear-off at $60 per square, $450 disposal and a $250 permit.

The module orders 22 squares with waste, 66 bundles, 51.8 ft of ridge cap, 180.8 ft of drip edge, 3 underlayment rolls and 2 rolls of ice and water shield. Materials total $4,201.61 and the whole job $11,101.61.

$151.03 is 1.4% of the $11,101.61 job. On the 24-month change the same lines gain $302.48. Roofing is a labor story: labor and tear-off are 59.9% of this estimate, and nothing in the producer data touches them. The number to watch is the recent slope. The asphalt roofing index bottomed at 346.394 in March 2026 and has climbed 8.0% in five months since, so most of the year's rise came recently.

Wire and drywall, per $1,000

For trades where a job-level model would mean guessing quantities, a rate is more honest. $1,000 of copper building wire at August 2025 producer prices is $1,272.44 at August 2026 prices, and $1,455.27 against August 2024. On a panel upgrade or a rewire, the wire line is the one to question in a quote that is more than a few months old.

$1,000 of gypsum products a year ago is $1,001.71 now. Drywall is the one big interior material with no inflation story this year, so a drywall quote that went up noticeably since last fall is pricing something other than board: labor, delivery or margin. The drywall calculator will give you the sheet count to check it against.

The market around the numbers

Input costs are rising while building activity is not. Census reported privately owned housing starts at a seasonally adjusted annual rate of 1,275,000 in August 2026, 2.6% below July and 1.2% below August 2025. Census attaches margins of plus or minus 12.0% and 10.8% to those two changes, so statistically the pace is flat. Single-family starts were 918,000, and permits were 1,394,000, 3.5% above a year earlier.

Financing got more expensive at the same time. Freddie Mac's 30-year fixed rate averaged 6.95% for the week of September 17, 2026, up from 6.76% the week before and 6.26% a year earlier.

Put together, that points to cost push rather than a demand boom. When builders are busy, suppliers can pass increases through fast. When starts are flat and borrowing costs rise, there is more room to negotiate on the lines a contractor controls, and less on metal, where the producer increase is large and steady.

What to do about it

Lock the quote, and check its date

A contractor quote prices materials on the day it is written. Ask how long it holds and get the answer in writing. A short hold on a job heavy in lumber or wire tells you the contractor expects to reprice. If a quote from spring is still on your desk, reprice it yourself before signing: multiply its lumber, wire and steel lines by the change in the matching index since the quote month. That is the same method used above, on your numbers.

Buy now or wait: the lumber math

The deck's lumber line is $2,077.23. Here is what three months of waiting does to it under three readings of the data:

If softwood lumber keeps the average monthly pace of the last six months, 1.46% a month from February's 270.326 to August's 294.899, the line grows $92.36 in three months. If August's 1.9% decline repeats for three months, it shrinks $114.97. Buying now and holding the cash tied up for those three months costs $36.09 at 6.95%, the current 30-year mortgage average, used here as a stand-in for what the money costs you.

The upside and downside are about the same size, and July's 6.4% jump followed by August's drop shows how noisy the series is. That is a coin flip, and coin flips are not worth stacking lumber in a driveway for, where it can warp, check or walk away. Lock a price with the supplier or the contractor instead, and let them hold the inventory.

Buy now or wait: copper and steel

The metal series look different. Copper wire has risen from 537.87 in February to 602.48 in August, an average of 1.91% a month; on $1,000 of wire, three more months at that pace adds $58.36. Steel mill products averaged 2.69% a month over the same six months, which is $82.79 on $1,000 in three months, and the index has not posted a monthly decline since November 2025.

Against a carrying cost of about $17 per $1,000 for three months at 6.95%, locking early wins on the recent trend. That is a trend line, and metals can reverse. But when a series has risen for nine months straight, the burden of proof sits with waiting. If you have a job with a big wire or rebar line starting this fall, ask the electrician or concrete contractor to buy or price those materials at contract.

Price escalation clauses, done right

On bigger jobs a contractor may offer a fixed price with a material escalation clause, or ask for one. A clause is fair to both sides only when every term is pinned to something published. Write in the BLS series ID (for rebar, WPU1074051; a phrase like "the price of steel" settles nothing), the base month and its value, and which print counts. BLS marks recent months preliminary and revises them for up to four months, so say whether the first-published value or the value four months later settles the bill.

Then set a threshold and a direction. Here is how the numbers work on a hypothetical $8,000 rebar line with a base of 385.370, the August 2026 preliminary value, and a 5% threshold. If the index reads 8% higher when the steel is bought, about 416.2, an "excess over threshold" clause adds 3% of $8,000, or $240. A "full change once triggered" clause adds 8%, or $640. Same index, same threshold, a $400 difference from one sentence of contract language. Ask for a cap, and make the clause work in both directions so a falling index gives money back.

Keep clauses to the volatile lines. Copper wire, steel and lumber qualify on this year's data. Ready-mix concrete, gypsum and asphalt shingles have moved less than 4% in twelve months, and an escalation clause on them mostly adds paperwork.

How this guide will be updated

BLS releases September 2026 producer prices on October 15, 2026. This page tracks the same nine series by ID each month, so the table and the project math can be rerun without changing the method. Expect the May through August values to be revised as they age past the preliminary window; when they are, the revised values replace these.

To run the numbers for your own job, start with the deck cost calculator, the concrete calculator or the roofing calculator, enter the prices from your quote, and apply the index change from the table to each material line.