Measurements of ceiling heights (Nat)

Clause 3.8.2.2 of BCA Volume Two sets out the minimum requirements for ceiling heights in dwellings. BCA 2011 now includes a diagram and accompanying notes that makes it very clear how to measure ceiling heights for the different areas in a house.

Please note the actual standards for measuring ceiling height have not changed. This diagram has simply been provided to give clarity as to where and how the measurements are to be applied.

The letters represent the following minimum dimensions:

A = 2.4m Habitable room (excluding a kitchen – 2.1m)
B = 2.4m Habitable room - two-thirds of the floor area
C = 2.1m Non -habitable room two-thirds of the floor area
D = 2.2m An attic to be habitable - two-thirds of the floor area
E = 1.5m Calculating the floor area of a room or space, any ceiling height of 1.5m is excluded
F = 2.0 Stairs (measured vertically above the nosing line)
The combined dimensions of G must not exceed one-third of the floor area (See E above) of the room or space.

 
For clarity, the supporting clause 3.8.2.2 of BCA Volume 2 is set out below. Subject to any planning controls that may be applied by the local council, this clause sets out the minimum ceiling heights for habitable rooms in a new dwelling.

3.8.2.2 - Ceiling heights

Ceiling heights (see Figure 3.8.2.1) must be not less than—
(a) in a habitable room excluding a kitchen – 2.4m; and
(b) in a kitchen – 2.1m; and
(c) in a corridor, passageway or the like – 2.1m; and
(d) in a bathroom, shower room, laundry, sanitary compartment, airlock, pantry, storeroom, garage, car parking area or the like — 2.1 m; and
(e) in a room or space with a sloping ceiling or projections below the ceiling line within—

i. a habitable room—

A.	in an attic — a height of not less than 2.2 m for at least two-thirds of the floor area of the room or space; and
B.	in other rooms — a height of not less than 2.4 m over two-thirds of the floor area of the room or space; and

ii. a non- habitable room— a height of not less than 2.1 m for at least two-thirds of the floor area of the room or space,
and when calculating the floor area of a room or space, any part that has a ceiling height of less than 1.5m is not included; and

Reference: Clause 3.8.2.2 and Figure 3.8.2.1 Building Code of Australia 2011 Volume Two Class 1 and 10 buildings

_{DISCLAIMER – the above is intended to provide general information in summary form. The contents do not constitute specific advice and should not be relied upon as such. Formal specific advice should be sought by members with respect to particular matters before taking action.}