Part 3.12.4 Air Movement
This Part applies to a habitable room in a Class 1 building.
220.127.116.11 Air movement
Air movement must be provided to habitable rooms in accordance with Table 18.104.22.168.
Air movement required by (a) may be provided through an opening from an adjoining room (including an enclosed verandah) if—
the adjoining room is not a sanitary compartment; and
the opening between the adjoining room and the habitable room complies with Table 22.214.171.124 as if it were a ventilation opening to the habitable room or a proportion thereof if some ventilation is provided from another source; and
the ventilation opening to the adjoining room complies with Table 126.96.36.199 for the floor area of the adjoining room and the proportion of the habitable room that is ventilated from the adjoining room.
The requirements of (a) do not apply to buildings in Region D severe tropical cyclone areas (see Figure 188.8.131.52) provided the external walls are shaded with a verandah, balcony, eaves, carport or the like that projects at a minimum angle of 15 degrees in accordance with Figure 184.108.40.206.
Table 220.127.116.11 PROVISION FOR AIR MOVEMENT
|Climate zones||Minimum total ventilation opening area as a percentage of the floor area for each habitable room|
|Without a ceiling fan or evaporative cooler||With a ceiling fan||With an evaporative cooler|
|1||10%||7.5%||10% (see Note)|
|2||10%||7.5%||10% (see Note)|
|5||7.5%||5%||7.5% (see Note)|
|6, 7, 8||As by Part 3.8.5|
|Note: Because evaporative coolers are less effective than ceiling fans in more humid locations, the requirement for ventilation opening in climate zones 1, 2 and 5 with an evaporative cooler is the same as without one.|
In humid locations, such as Darwin and Cairns, evaporative coolers would not provide the same cooling effect as in dryer climates. Although they would provide some benefit from the air movement if operated in a “fan-only” mode, they would cause discomfort, possible condensation and possible mould growth if operated in an evaporative “water-on” mode. However, even though a concession is not given in climate zones 1, 2 and 5, there are locations, particularly in climate zone 5, where evaporative coolers would be effective.
18.104.22.168 Ventilation openings
In climate zones 1, 2, 3, 4 and 5, the total ventilation opening area required by Table 22.214.171.124 to a habitable room must—
be connected by a breeze path complying with (b) to another ventilation opening in another room or space; or
be provided by a minimum of two ventilation openings located within the same habitable room, with each ventilation opening having an area of not less than 25% of the area required by Table 126.96.36.199.
A breeze path required by (a)(i) must—
pass through not more than two openings in the internal walls with each opening having an area of not less than 1.5 m2; and
have a distance along the breeze path between ventilation openings of not more than 20 m.
- Ventilation openings should be designed to allow the interior of the building to take full advantage of any natural breeze. Careful consideration should be given to the type and location of openings to ensure optimum effect is achieved and that internal “dead air pockets” are avoided.
- An opening may serve more than one breeze path.
- Two openings are stated in (b)(i) as the limit of the number of openings permitted in a breeze path. These are typically doorways. Larger openings, such as those between adjoining lounge and dining areas in the same space are unlikely to restrict air movement significantly.
188.8.131.52 Ceiling fans and evaporative coolers
Ceiling fans or evaporative coolers required to comply with 184.108.40.206, Table 220.127.116.11 or Table 18.104.22.168 must—
be permanently installed; and
have a speed controller; and
for ceiling fans, serve the whole room, with the floor area that a single fan serves not exceeding—
15 m2 if it has a blade rotation diameter of not less than 900 mm; and
25 m2 if it has a blade rotation diameter of not less than 1200 mm.