Vulcan Materials Co. may be betting it can squeeze $1 billion more out of a takeover bid that’s already the most expensive for a U.S. building material company, according to a Dec. 14 Bloomberg report.

Martin Marietta Materials Inc.’s $4.8 billion hostile offer for Birmingham, Ala.-based Vulcan values the largest American producer of crushed stone at 24 times earnings before interest, taxes, depreciation and amortization, according to the Bloomberg report. The multiple is the highest on record for an acquisition greater than $500 million of a U.S. maker of building materials such as cement, according to data compiled by Bloomberg that includes net debt.