Ventilation Drawing Reference
Exhaust Capacities
The table gives approximate exhaust flow capacities for a range of stack heights (ridge height above ground), wind speeds at the ridge and internal temperature between ground level and ridge.
Exhaust Flow Litres/Second/Lineal Metre
Achievement of these flows requires sufficient openings to provide free airflow into the building.
Dimond Fixed Ridge Ventilators are available in Zincalume, Colorsteel, ColorCote and Aluminium material to match the roofing material chosen.
Sizes up to and including the 300 throat can be fixed directly onto the roof without bracketing using hex head self-drilling screws, the same as the roof profile on every rib. Sizes above this require a bracketing system.
| U.L.S Wind Load | Mild Steel Bracket Size (mm) | Maximum Bracket Spacing (mm) |
| 1.0 kPa | 40 x 5 | 600 |
| 2.0 kPa | 40 x 8 | 600 |
| 3.0 kPa | 40 x 8 | 400 |
U.L.S = Ultimate Limit State Load
