The safe working load is the load capacity of the fixings using the required factor of safety (FOS) under the British standard, however, given the variability in the quality of the wall and the installation, it would be sensible to lower the capacity of the fixings to a recommended load.
Shear Load
Tension Load
Cantilever
|
|
Shear kg |
Tension kg |
|---|---|---|
| Ultimate Capacity |
130 |
65 |
| SWL | 65 | 32.5 |
| Recommended Load | 43 | 21.6 |
Recommended load for hanging hooks = 20kg
F.O.S = Factor of Safety
| T-Bolt | Cantilever (based on 2 brackets and 4 fixings) *300mm leg down the wall and 200mm shelf from the wall, loaded at 100mm* |
|---|---|
| Safe Working Load for shelf brackets | 85kg |
- Weights shown indicate safe working loads. Independently tested on 15mm plasterboard. Any plasterboard over 15mm thick, will require a longer M5 screw.
- Not suitable for full motion TV brackets.
- Recommended load for the picture hanging hooks = 20kg
- For safety ensure the condition of the plasterboard is never damp or damaged before installation. The fixing should not be fixed to weak walls and ceilings.
Independent Testing Conditions;
The independent test wallpanels were fabricated and then loaded at an independent laboratory to determine the failure load at which the fixing pulled out of the plasterboard.
This determined the Ultimate load. The determine load can be used day to day, a factor of safety is applied to the ultimate load to define the safe working load for the fixing. These factors are defined by British standards.
Because the initial tests were conducted in laboratory conditions it would be advisable to apply an additional factors to create a recommended load to accommodate the variability in the walls moisture content quality of construction etc.