NCC 2025 Volume Two 10.8.2 — Exhaust Systems Calculator

Assumptions

1. All rangehoods are 150mm diameter — the most common size. Some are 125mm or 200mm; in these cases select ducting and a vent of appropriate diameter.
2. A 3m length of ducting is sufficient. In some cases, longer ducting may be required.
3. Flexible ducting will be used. Semi-rigid ducting is more difficult to install but has superior ventilation efficiency.
4. For roof vents, use of low profile roof vents is assumed. Other options such as compact roof vent, mushroom cowl and pipe or roof vent kits may be used.
5. For eave vents, the S150ABAL vent is assumed. Other options include the 3-way S1503BAL, 5-way S150BAL and the GIV150 grille vent.
6. For wall vents, the BV150 brick vent is assumed. Other alternatives include the WV150DB double brick vent, GIV150 grille vent and the GAV150 gravity vent.