back
CALCULATING LOUVRE and GRATING SPANS Notes:
Wind Loads = Wind Velocity X Reduction Factor
Pedestrian traffic manitenance loads = 2.5kPa
Public assembly type loads = 5.0 kPa
The reduction factors for the grating and louvre
profiles are for use on wind loads only and are based on a combination
of the porosity of the profile and the orientation of the product
on the building.
Loads are calculated for simple spans with a maximum deflection =
Span ÷ 200 mm for grating and trafficable louvre sections type.
Loads are calculated for simple spans with a maximum deflection =
Span ÷ 150 mm for non-trafficable louvre sections.
For trafficable situations cross bars are to be installed in the upper
plane.
For HC grating sections multiply span x 0.8.
For serrated flat bar sections allow extra 5mm on selected load bar
depth.
HA205 not available serrated.
Wind Velocities Notes:
The intention of calculation procedure is to provide
an estimate of wind pressures on an array of screens, based on a few
simplifying assumptions.
1. The basic pressure coefficient is intended to take into account
the influence of the shape of the building on the pressure experienced
by the screens. It is a conservative approximation and allows the
pressures in the table to be applicable for the following cases.
1.1 Screens placed on any wall of a building.
1.2 Screens placed horizontally, away from the edge of a building.
2. Screens positioned near building corners within a proximity of
0.2 x smallest building plan dimension will experience pressures up
to 2 times the above tabulated pressures (see diagram
A).
3. The basic wind speed is a peak 3-second gust with a 50-year return
period, measured at 10 metres height in a terrain category 2.
4. The basic wind pressure is the freestream pressure at 10m in terrain
category 2.
5. Terrain category classifications are based on AS1170.2-2002.
6. Wind speeds are based on data from AS1170.2-2002 and Wind
Loading on Structures by J.D. Holmes.
For free standing screens or screens located above 20 metres in height DO NOT use this table - specialist façade engineering advice is required

