The cost of construction materials in the U.S. continues to climb as inflation, tariffs and the conflict in Iran converge to make commodities like energy and lumber more expensive.

Input prices in April rose 6.2% since January, according to an analysis released Wednesday by Associated Builders and Contractors. The analysis was based on data from the Bureau of Labor Statistics’ producer price index.

“Construction input prices surged again in April,” ABC Chief Economist Anirban Basu said in a release. “Input prices have now risen more during the first four months of 2026 (6.2%) than over the prior three years (4.8%).”

Construction materials were 7% more expensive last month than in April 2025. For nonresidential materials, costs were up 7.4% year-over-year. Between March and April, overall construction input prices ticked up 1.7%, while nonresidential prices were up 1.8%.

Breaking down the data by type of material shows that rising energy costs are playing a key role in how the overall price index is shifting.

Between March and April, crude petroleum skyrocketed 11.3%, the sharpest rise of any commodity. The second-steepest rise was for unprocessed energy materials, the cost of which rose by 9.2% month-over-month. Natural gas rose by 4.9%.

But some other materials also showed steep price spikes in April. The cost of softwood lumber rose by 5.5%, and hot rolled steel bars increased by 4.1%. Steel mill products and industrial controls equipment rose by 3.8%.

Energy prices are also leading the price index surge year-over-year. Crude petroleum is up 61.8%, natural gas is up 27.3%, and unprocessed energy materials are up 48.9% since April 2025.

Construction industry prices are part of a nationwide inflationary story. Wholesale inflation increased by 1.4% in April compared to March, double the increase of the month prior and substantially exceeding economists’ expectations of a 0.5% increase, The Wall Street Journal reported.