Income Tax Assessment Act 1997
A dwelling includes:
(a) a unit of accommodation that:
(i) is a building or is contained in a building; and
(ii) consists wholly or mainly of residential accommodation; and
(b) a unit of accommodation that is a caravan, houseboat or other mobile home; and
(c) any land immediately under the unit of accommodation. 118-115(2)
However, except as provided in section 118-120 , a dwelling does not include any land adjacent to a building.