FireWall panels will provide the following U values:
| FireWall | FireWall Extra | |
| Thickness | U Value | U Value |
| 75 | 0.52 | 0.56 |
| 100 | 0.39 | 0.42 |
| 125 | 0.31 | 0.34 |
| 150 | 0.26 | 0.28 |
| 175 | 0.22 | 0.24 |
| 200 | 0.20 | 0.21 |
The above U values have been calculated using a plain element approach and do not take into account any thermal bridging through the joint.