| OAOldcastle Architectural West INC | Rosenberg | TX | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Dallas | TX | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Austin | TX | — | ◇ UNVERIFIED |
| OCOldcastle Coastal Concrete Products | West Palm Beach | FL | — | ◇ UNVERIFIED |
| OCOldcastle Coastal Concrete Products | Orlando | FL | — | ◇ UNVERIFIED |
| OCOldcastle Coastal, INC. | Zephyrhills | FL | — | ◇ UNVERIFIED |
| OCOld Castle Infrastructure | Fuquay Varina | NC | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Wilsonville | OR | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Platteville | CO | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Topeka | KS | — | ◇ UNVERIFIED |
 Oldcastle Infrastructure INC. | Fredericksburg | VA | — | ◇ UNVERIFIED |
| Oldcastle Infrastructure INC. - Courtland | Courtland | MN | — | ◇ UNVERIFIED |
| OMOldcastle Matt Stone Holdings Incorporated | Cowpens | SC | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Kalamazoo | MI | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Idaho Falls | ID | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Houston | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Mansfield | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Lebanon | TN | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Avon | CT | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Lakeside | CA | — | ◇ UNVERIFIED |
| OPOldcastle Precast Brookshire Plant | Brookshire | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Littleton | CO | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Medley | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Orlando | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | North Fort Myers | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Chandler | AZ | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Middle Island | NY | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC. | Edgewood | MD | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. - Bellingham | Bellingham | WA | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC - Concord | Concord | NC | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. - Jacksonvillesp | Jacksonville | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast Incorported | Rehoboth | MA | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. - Tallahasseesp | Midway | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast San Antonio Plant | San Antonio | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast Telco | Newnan | GA | — | ◇ UNVERIFIED |
| OROldcastle Retail INC | Oxford | MA | — | ◇ UNVERIFIED |
| OROldcastle Retail, INC. | Jacksonville | FL | — | ◇ UNVERIFIED |
| OROldcastle Retail INC (dba Bonsal American) | Canaan | CT | — | ◇ UNVERIFIED |
| OROldcastle Retail INC (dba Bonsal American) | Lilesville | NC | — | ◇ UNVERIFIED |
| OPOrchard Park Plant | Orchard Park | NY | — | ◇ UNVERIFIED |
| OOriskany | Oriskany | NY | — | ◇ UNVERIFIED |
| OPOrlando Paving Plant #11 | Orlando | FL | — | ◇ UNVERIFIED |
| OPOrlando Paving Plant #5 | Apopka | FL | — | ◇ UNVERIFIED |
| OCOwatonna Construction CO - Masonry | Medford | MN | — | ◇ UNVERIFIED |
| OCOwens-corning CORP | Summit | IL | — | ◇ UNVERIFIED |
| OCOwens Corning - Denver Roofing Plant | Denver Area | CO | — | ◇ UNVERIFIED |
| OFOwens-corning Fiberglass Trumbull * | Medina | OH | — | ◇ UNVERIFIED |
| OCOwens Corning Memphis Asphalt Plant | Memphis | TN | — | ◇ UNVERIFIED |
| OCOwens Corning - Minneapolis Plant | Minneapolis | MN | — | ◇ UNVERIFIED |
| OCOwens Corning Roofing and Asphalt LLC / 3400 Ne 4th St Asphalt Plant | Oklahoma City | OK | — | ◇ UNVERIFIED |
