Fire Resistance Table
Fire resistance of concrete masonry walls is a function of aggregate type and equivalent thickness of the masonry units. The ratings in the charts below are calculated using the actual percent of solids in the various sizes of blocks as manufactured by Capitol Concrete Products. The ratings are based on test information obtained from Underwriters’ Laboratories Inc., the National Bureau of Standards, the Portland Cement Association, and the Uniform Building Code.
For additional technical information, visit the Tech Bulletins offered by the National Concrete Masonry Association (NCMA), or contact our sales staff for assistance.
Fire Resistance Table
Fire resistance of concrete masonry walls is a function of aggregate type and equivalent thickness of the masonry units. The ratings in the charts below are calculated using the actual percent of solids in the various sizes of blocks as manufactured by Capitol Concrete Products. The ratings are based on test information obtained from Underwriters’ Laboratories Inc., the National Bureau of Standards, the Portland Cement Association, and the Uniform Building Code.
For additional technical information, visit the Tech Bulletins offered by the National Concrete Masonry Association (NCMA), or contact our sales staff for assistance.
| FIRE RESISTANCE IN HOURS | ||||
| AS MANUFACTURED BY CAPITOL CONCRETE | PER- CENT SOLID | EQUIVALENT THICKNESS | LIGHT- WEIGHT EXP. SHALE | NORMAL- WEIGHT LIMESTONE |
| BRICK | 100.0 | 3.63 | 2.0 | 1.0 |
| 4″ STANDARD CORES | 73.4 | 2.66 | 1.0 | 1.0 |
| 4″ SOLID | 100.0 | 3.63 | 2.0 | 1.0 |
| 6″ STANDARD CORES | 54.5 | 3.07 | 1.0 | 1.0 |
| 6″ SPECIAL 2-HOUR CORES | 70.0 | 3.93 | 2.0 | 1.0 |
| 6″ SOLID | 100.0 | 5.63 | 4.0 | 3.0 |
| 8″ STANDARD CORES | 53.0 | 4.04 | 2.0 | 2.0 |
| 8″ SPECIAL 4-HOUR CORES | 75.0 | 5.72 | 4.0 | 3.0 |
| 8″ SOLID | 100.0 | 7.63 | 7.0 | 6.0 |
| 12″ STANDARD CORES | 48.7 | 6.66 | 4.0 | 3.0 |
| 12″ SPECIAL 3 CORE | 55.9 | 6.80 | 4.0 | 4.0 |
For additional information see:
- Concrete Masonry Manual published by Expanded Shale, Clay and Slate Institute. section 9 – “Fire Resistance” pages 27, 28 and 29
- Concrete Masonry handbook published by Portland Cement Association “Fire Resistance of Concrete Masonry” pages 12 and 13
- Tek 35c “Fire Safety with Concrete Masonry” published by National Concrete Masonry Association
- Uniform Building Code – section 4302(a) – table 43-b, 1985 edition and 1986 supplement
| FIRE RESISTANCE IN HOURS |
||||
| AS MANUFACTURED BY CAPITOL CONCRETE | PER- CENT SOLID | EQUIVALENT THICKNESS | LIGHT- WEIGHT EXP. SHALE | NORMAL- WEIGHT LIMESTONE |
| BRICK | 100.0 | 3.63 | 2.0 | 1.0 |
| 4″ STANDARD CORES | 73.4 | 2.66 | 1.0 | 1.0 |
| 4″ SOLID | 100.0 | 3.63 | 2.0 | 1.0 |
| 6″ STANDARD CORES | 54.5 | 3.07 | 1.0 | 1.0 |
| 6″ SPECIAL 2-HOUR CORES | 70.0 | 3.93 | 2.0 | 1.0 |
| 6″ SOLID | 100.0 | 5.63 | 4.0 | 3.0 |
| 8″ STANDARD CORES | 53.0 | 4.04 | 2.0 | 2.0 |
| 8″ SPECIAL 4-HOUR CORES | 75.0 | 5.72 | 4.0 | 3.0 |
| 8″ SOLID | 100.0 | 7.63 | 7.0 | 6.0 |
| 12″ STANDARD CORES | 48.7 | 6.66 | 4.0 | 3.0 |
| 12″ SPECIAL 3 CORE | 55.9 | 6.80 | 4.0 | 4.0 |
For additional information see:
- Concrete Masonry Manual published by Expanded Shale, Clay and Slate Institute. section 9 – “Fire Resistance” pages 27, 28 and 29
- Concrete Masonry handbook published by Portland Cement Association “Fire Resistance of Concrete Masonry” pages 12 and 13
- Tek 35c “Fire Safety with Concrete Masonry” published by National Concrete Masonry Association
- Uniform Building Code – section 4302(a) – table 43-b, 1985 edition and 1986 supplement
