| Onduline North America |
Fredericksburg, Virginia |
| Oneonta Block Company |
Oneonta, New York |
| OPCO, Inc. |
Latrobe, Pennsylvania |
| OPPLE Lighting |
Minhang Qu, Shanghai Shi |
| Optimum Window Manufacturing Corporation |
Ellenville, New York |
| Orbit Industries, Inc. |
Los Angeles, California |
| Orca Manufacturing, Inc. |
Hurlock, Maryland |
| Oregon Door |
Winston, Oregon |
| Oregon Shepherd, LLC |
Ranier, Oregon |
| Organic Lighting Systems, Inc. |
Riverside, California |
| Organo Bulb |
Dallas, Texas |
| Orion Energy Systems, Inc. |
Manitowoc, Wisconsin |
| Ortech Industries Inc. |
Surrey, British Columbia |
| Oshkosh Door Company |
Oshkosh, Wisconsin |
| OSRAM SYLVANIA |
Versailles, Kentucky |
| OSRAM SYLVANIA |
Wilmington, Massachusetts |
| OVE Decors |
Laval, Quebec |
| Overdrive Electronics Pvt. Ltd. |
Fairfield, New Jersey |
| Overly Door Company |
Greensburg, Pennsylvania |
| Owens Corning |
Lakeland, Florida |
| Owens Corning |
Sedalia, Missouri |
| Owens Corning |
Fresno, Texas |
| Owens Corning |
Newark, Ohio |
| Owens Corning |
Waxahatchie, Texas |
| Owens Corning |
Gresham, Oregon |
| Owens Corning |
Nephi, Utah |
| Owens Corning |
Savannah, Georgia |
| Owens Corning |
Toledo, Ohio |
| Owens Corning |
Mt Vernon, Ohio |
| Owens Corning |
Jacksonville, Florida |
| Owens Corning |
Kearny, New Jersey |
| Owens Corning |
Feura Bush, New York |
| Owens Corning |
Brookville, Indiana |
| Owens Corning |
Compton, California |
| Owens Corning |
Minneapolis, Minnesota |
| Owens Corning |
Elroy, Arizona |
| Owens Corning |
Duncan, South Carolina |
| Owens Corning |
Irving, Texas |
| Owens Corning |
Rockford, Illinois |
| Owens Corning |
Tallmadge, Ohio |
| Owens Corning |
Kansas City, Kansas |
| Owens Corning |
Oklahoma City, Oklahoma |
| Owens Corning |
Portland, Oregon |
| Owens Corning |
Newark, Ohio |
| Owens Corning |
Atlanta, Georgia |
| Owens Corning |
Denver, Colorado |
| Owens Corning |
Summit, Illinois |
| Owens Corning |
Fairburn, Georgia |
| Owens Corning |
Memphis, Tennessee |
| Owens Corning |
Houston, Texas |