Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7205374 | Two-part polyurethane adhesive for bonding insulation boards to a roof deck | John W. Fieldhouse, Joseph John Kalwara, John B. Letts | 2007-04-17 |
| 5950383 | Metal roof sealing system and method | Robert B. Williamson, John B. Letts | 1999-09-14 |
| 5516817 | Flame retardant modified asphalt-based material and products therefrom | Carter C. Slusher, Eric Ogren, William B. Gorman, Gary S. Thompson, Arthur M. Usmani | 1996-05-14 |
| 5468550 | EPDM roofing membrane with improved burn resistivity | James A. Davis, Brian S. Alexander, William F. Barham, Jr. | 1995-11-21 |
| 5451621 | SBS-modified, asphalt-based material with resistance to crosslinking | Arthur M. Usmani, William B. Gorman, Gary S. Thompson | 1995-09-19 |