Sandstone Inc., dba Stoneworth Building Products participates in the Intertek Roof Impact Certification Program and the locations and concrete roofing tile products described below are certified for performance as noted:
| Location |
Product |
Performance Level |
Standard |
| Shawnee, KS |
Oxford |
3 |
FM 4473-11 |
| Venetian – Armor |
3 |
| Venetian – Standard |
3 |
| Nottingham |
3 |
| Kensington |
3 |
| Cambridge |
3 |
| Bristol |
3 |
