 CARY, N.C.--BUSINESS WIRE--Cornerstone Building Brands, Inc. NYSE: CNR the Company, the largest manufacturer of exterior building products in North America, announced today that it completed the previously announced sale of its Insulated Metal Panels IMP business to Nucor Insulated Panel Group, Inc. and certain of its subsidiaries collectively, Nucor in a cash transaction for 1 billion, subject to customary adjustments. The Company expects post-tax transaction proceeds to be us 