U.S. company rebuts drywall claim

National Gypsum Co., the Charlotte-based building materials maker, said its products aren’t the cause of the problems in George and Brenda Brincku’s Lee County home. The couple claimed drywall corroded the metal in their home and emitted sulfuric odors, but a National Gypsum investigation found no problem with the plasterboard in the house. The couple said all their drywall was made by National, though almost all other complaints have focused on Chinese-made products that prompted calls for investigations at local, state and federal levels.