Australian Capital Territory Numbered Regulations

BUILDING REGULATIONS 2004 (NO 34 OF 2004) - REG 16

An alteration of a building is a substantial alteration if—

        (a)     the aggregate volume of the proposed alteration and any other alteration made to the building during the 3 years immediately before the day the application for building approval of the alteration is made is more than 50% of the volume of the original building; and

        (b)     the volume of a building is measured by reference to roof and outer walls.

Example of effect

1     A house is extended by 70%. The whole building must comply with this Act, not just the extension (see par (a)).

2     A sunroom is added to a building, adding only 10% to the building. The sunroom must comply with this Act, not the rest of the building (see par (b)).

3     Two shops in a mall are to be combined to form a café. The building work involves replacing all the shops' fitout, including all fixtures, the glazed shopfront walling and ceiling and removal of the common wall. In the 3 years immediately before the date the application for building approval is made, other shops in the mall have been altered similarly. The total volume of the refitted shops, with the volume of the café, is more 50% of the volume of the mall. The whole mall must comply with this Act, not just the café.

4     A photocopier room is to be added to an office building. In the 3 years immediately before the date the application for building approval is made the building has often had parts of its fitout altered. Open plan cubical work stations were moved, enclosed meeting rooms were converted to open plan cubical workstations, 3 walls of another enclosed office were moved to make a hallway and new enclosed offices were created where open plan cubical workstations originally were.

              •     the 1 st alterations to the cubical workstations did not involve altering or erecting fixtures, so the alterations do not need to be included when working out the total volume of alterations to the building

              •     the cubicle work stations erected in place of the enclosed meeting rooms were fixtures, so the volume of each workstation, worked out by multiplying its usable floor area by the height of the floor or roof above, must be included in working out to the total volume of alterations to the building

              •     the removal of the 3 walls of the enclosed office to make a hallway prevent the room functioning as a room, so the volume of the room must be included in working out the total volume of the alterations to the building

              •     the walls erected to form a room or substantially enclosed space must be included to work out the total volume of the alterations to the building

However, the total of the volumes of the alterations made to the building, when added to the volume of the proposed photocopier room, amounted to 45% of the building, so only the proposed room has to comply with this Act, not the whole building.

5     A building contains a nightclub where a fire sprinkler system was installed 1 year ago. Plans now propose to upgrade the airconditioning system throughout the building. The volume of the sprinkler pipework and proposed airconditioning ducts are included in working out the total volume of alterations to the building, but the volume of the spaces they can sprinkle or ventilate is not included.

Note     An example is part of the regulations , is not exhaustive and may extend, but does not limit, the meaning of the provision in which it appears (see Legislation Act, s 126 and s 132).