ABCB Housing Provisions


NT Part 13.4 Building sealing

NT Part 13.4 Building sealing

NT 13.4.1 Application of Part 13.4New for 2022

This Part applies to—

  1. a Class 1 building; and
  2. a Class 10a building with a conditioned space.


This Part does not apply to:

  1. A building where the only means of air-conditioning is by using an evaporative cooler.
  2. A permanent building ventilation opening that is necessary for the safe operation of a gas appliance.
  3. A Class 10a building used for the accommodation of vehicles.

NT 13.4.2 Chimneys and fluesNew for 2022

The chimney or flue of an open solid-fuel burning appliance must be provided with a damper or flap that can be closed to seal the chimney or flue.

NT 13.4.3 Roof lightsNew for 2022

(1) A roof light must be sealed, or capable of being sealed, when serving a conditioned space.

(2) A roof light required by (1) must be constructed with—

  1. an imperforate ceiling diffuser or the like installed at the ceiling or internal lining level; or
  2. a weatherproof seal if it is a roof window; or
  3. a shutter system readily operated either manually, mechanically or electronically by the occupant.

NT 13.4.4 External windows and doorsNew for 2022

(1) A seal to restrict air infiltration must be fitted to each edge of an external door, openable window and other such opening when serving a conditioned space.

(2) The following need not comply with (1):

  1. An external louvre door, louvre window or other such opening.
  2. A window complying with the maximum air infiltration rates specified in AS 2047.

(3) A seal required by (1) may be a foam or rubber compressible strip, fibrous seal or the like.

NT 13.4.5 Exhaust fansNew for 2022

An exhaust fan must be fitted with a sealing device such as a self-closing damper, filter or the like when serving a conditioned space.

Explanatory information

An exhaust fan is considered to be adequately sealed if it is fitted with a filter such as the type commonly used in kitchen range hoods.

NT 13.4.6 Construction of ceilings, walls and floorsNew for 2022

(1) Ceilings, walls, floors and any opening such as a window frame, door frame, roof light frame or the like must be constructed to minimise air leakage in accordance with (2) when forming part of the external fabric a conditioned space.

(2) Construction required by (1) must be—

  1. enclosed by internal lining systems that are close fitting at ceiling, wall and floor junctions; or
  2. sealed at junctions and penetrations with—
    1. by close-fitting skirting, architraves, cornices; or
    2. expanding foam, rubber compressive strip, or caulking, or the like.

NT 13.4.7 Evaporative coolersNew for 2022

An evaporative cooler must be fitted with a self-closing damper or the like when serving a heated space.

Explanatory information

The self-closing damper should create an effective seal against air infiltration.