In this Part "dwelling" means any house, flat or other unit designed or adapted for living in.
For the purposes of this Part a building so designed or adapted is a "house" if it is a structure reasonably so called; so that where a building is divided into units so designed or adapted—
if it is so divided horizontally, or a material part of a unit lies above or below another unit, the units are not houses (though the building as a whole may be), and
if it is so divided vertically, the units may be houses.
Where a house which is divided into flsts or other units is a defective dwelling in respect of which a person is eligible for assistance, the fact that it is so divided shall be disregarded for the purposes of section 538(1)(a) (first condition for assistance by way of reinstatement: that the dwelling is a house).