NY -- Standard&Poor's CreditWire 7/3/97 -- Standard&Poor's today has affirmed its triple-'B'-minus corporate credit and senior unsecured debt ratings of Owens Corning. At the same time, Standard&Poor's has assigned its triple-'B'-minus rating to the company's $2 billion revolving credit facility maturing in 2002. Since the facility is unsecured, the bankers will fare the same as other senior creditors in the event of a default. Ratings incorporate the recently completed acquisition of Fibreboard Corp. for about $675 million, including assumption of $125 million of debt. The transaction is a plus for Owens Corning's business fundamentals, since it expands building materials offerings and enables the company to become a leading producer of vinyl siding. Debt increases