Spans & Loads
Nysan Skylight Louver Systems
Panel Span - The panel span in relation to the wind load (pressure or suction), can be calculated from the graph below:
SPAN & WIND LOAD CHART
| Parameter / System |
2” |
3” int. |
3” ext. |
3.5” int. |
3.5” ext. |
| Max. slat width (w) |
235”
6000mm |
195”
5000mm |
195”
5000mm |
155”
4000mm |
155”
4000mm |
| Max. distance between rack arms (x) |
36”
900mm |
55”
1400mm |
39”
1000mm |
60”
1500mm |
48”
1200mm |
| Max. slat overhang (y) |
16”
400mm |
20”
500mm |
10”
250mm |
10”
250mm |
6”
150mm |
| Max. support spacing (z) |
100”
2500mm |
100”
2500mm |
78”
2000mm |
78”
2000mm |
60”
1500mm |
| Max. rack arm length (l) |
235”
6000mm |
235”
6000mm |
235”
6000mm |
235”
6000mm |
235”
6000mm |
| Max. area – gear operated |
160 ft²
15 m² |
160 ft²
15 m² |
160 ft²
15 m² |
130 ft²
12 m² |
100 ft²
9 m² |
| Max. area - motorized |
215 ft²
20 m² |
215 ft²
20 m² |
215 ft²
20 m² |
170 ft²
16 m² |
130 ft²
12 m² |
Key parameters
Note: These are approximate dimensions and would need to be reviewed for each specific application (in particular where the installation is external).
The non-retractable rack arm system has been tested in a wind tunnel to speeds of up to approximately 110mph (180kph) and actual installations have survived hurricane force winds. Good performance of the system in strong winds is dependent upon the system being correctly installed and the design parameters, as are set out in the table above, being respected. Additionally, it is possible to install edge baffles to protect the exposed edges of the blind.
The other issues that need to be considered with an external system are ice and snow. The system has been tested with a simulated snow load and has also been installed in the past in locations where snow regularly falls. The system can cope with an imposed snow load – it is not appropriate, however, in locations where heavy snow falls occur regularly and the snow remains on the ground for periods in excess of a few days.
Ice is also an issue. The assembled rack arms are manufactured from aluminum extrusions and nylon components. If the mechanism is iced up, there is a risk of damage to the nylon components if the system is operated. It is possible to fit a control which prevents a motorized system from being operated if there is risk of ice. If, however, temperatures remain below freezing for reasonably long periods, external installation is probably not appropriate.
For additional information contact Nysan at 403.204.8675