WARRENVILLE, Ill. — A commodity surcharge will be added to the price of IC Bus models beginning Sept. 15.

The school and commercial bus manufacturer said in an announcement Thursday that the surcharge is necessary because market conditions and global demand have raised commodity prices to “historical highs.”

“Market prices, which have retreated some but remain higher than the 2009 and 2010 levels, combined with global expansion and investor speculation, are driving prices higher,” the company’s announcement said. “The continued increase in the price of metals, which are essential to bus production, is necessitating price increases up to $1,495.”

Prices have soared for such bus manufacturing commodities as rubber, steel, copper and platinum. IC Bus said that it is working to alleviate the higher commodity prices by absorbing as many costs as possible.

“Our efforts to mitigate price increases through manufacturing efficiencies have allowed for us to absorb some of the increases, but we could not absorb them all,” IC Bus President John McKinney said. “Global commodity increases are affecting all manufacturing, and unfortunately, they are beyond our control, leaving us no choice but to share those additional costs with the customer.”

Steel and its derivatives account for more than 41 percent of the material value of a bus, according to the company. Steel prices have increased between 60 and 116 percent since 2009. Platinum, which makes up almost 11 percent of a bus’ material value, has gone up 46 percent since 2009.

“These costs have a significant, direct impact on the raw materials needed to build buses,” McKinney said. “We will continue to closely monitor market conditions and do everything possible to manufacture the best quality buses at the most efficient prices for our customers.”