Ward Nye, CEO, Martin MariettaScott Mlyn | CNBCMartin Marietta Materials said on Monday it would merge with limestone supplier Lhoist North America in a cash-and-stock deal worth $13.5 billion, as ⁠the building ‌materials firm looks to tap growing demand ⁠for lime products.ShareShares ⁠of the Raleigh, North Carolina-based company were down 5% in morning trade.Martin Marietta will use a mix of $7 billion in cash along with shares ‌valued at $6.5 billion to fund the deal, the company said. It expects to realize about $85 million in annual run-rate cost synergies.CEO Ward Nye said demand for high-quality lime products is expected to remain resilient for decades to come, due to investment in infrastructure, advanced manufacturing, energy development and industrial ⁠expansion in the U.S.There has been a surge in dealmaking in the U.S. building-products industry ‌as the data center construction business booms, along ‌with new housing, repairs and renovations.Last week, Ireland's CRH said it would acquire Arcosa in an all-cash deal valued at about $8.5 billion, in a bid ⁠to capitalize on rising demand for U.S. energy and utility infrastructure.Lhoist's Berghmans ⁠family - which owns the privately held Lhoist Group, a ⁠Belgian industrial company - would own roughly 15% of Martin Marietta upon the deal's close.The transaction would add quarries, ​production facilities, distribution terminals and 2 billion ‌tons of limestone reserves in Sun Belt metropolitan corridors to Martin Marietta's portfolio.Morgan Stanley analyst Angel Castillo said ​while the deal adds more end markets ‌and some complexity, it comes with material expansion into attractive infrastructure markets which "we view as a high-quality form of diversification."Lhoist North America makes hi-calcium lime, dolomitic lime and industrial mineral products used in domestic steel manufacturing, infrastructure and heavy non-residential construction across North America.The deal is ​expected to be completed in the ‌second half of 2026, subject to regulatory approvals.