NCC 2022 Volume One - Building Code of Australia Class 2 to 9 buildings
Search the National Construction Code editions
Classification
Building class 1a Building class 1b Building class 2 Building class 3 Building class 4 Building class 5 Building class 6 Building class 7a Building class 7b Building class 8 Building class 9a Building class 9b Building class 9c Building class 10a Building class 10b Building class 10c

Filter

Classification
Building class 1a Building class 1b Building class 2 Building class 3 Building class 4 Building class 5 Building class 6 Building class 7a Building class 7b Building class 8 Building class 9a Building class 9b Building class 9c Building class 10a Building class 10b Building class 10c

F3

Part F3 Roof and wall cladding

Part F3 Roof and wall cladding

Introduction to this Part

This Part is intended to minimise the risk of water, including surface water and rainwater, entering the building and causing musty, damp and unhealthy conditions or damaging building elements by corrosion or other degradation. It is also intended to prevent water redirected away from the outside of the building damaging nearby properties.

Objectives

The Objective of this Part is to—

  1. safeguard occupants from illness or injury and protect buildings from damage caused by—
    1. ingress of water from outside the building; and
    2. the accumulation of internal moisture in the building.

Functional Statements

A building is to be constructed to prevent penetration of water from the outside.

Performance Requirements

A roof and external wall (including openings around windows and doors) must prevent the penetration of water that could cause—

  1. unhealthy or dangerous conditions, or loss of amenity for occupants; and
  2. undue dampness or deterioration of building elements.

Limitations

F3P1 does not apply to—

  1. a Class 7 or 8 building where in the particular case there is no necessity for compliance; or
  2. a garage, tool shed, sanitary compartment, or the like, forming part of a building used for other purposes; or
  3. an open spectator stand or open-deck carpark.

Verification Methods

(1) Compliance with F3P1 for weatherproofing of an external wall is verified when—

  1. a prototype passes the procedure described in (2); and
  2. the external wall—
    1. has a risk score of 20 or less, when the sum of all risk factor scores are determined in accordance with Table F3V1a; and
    2. is not subjected to an ultimate limit state wind pressure of more than 2.5 kPa; and
    3. includes only windows that comply with AS 2047.

(2) The test procedure referred to in (1)(a) must be as follows:

  1. The test specimen is in accordance with the requirements of (3).
  2. The test procedure is in accordance with the requirements of (4) or (5) as applicable.
  3. The test specimen does not fail the criteria in (6).
  4. The test is recorded in accordance with the requirements of (7).

(3) Test specimen: The test specimen must incorporate—

  1. representative samples of openings and joints, including—
    1. vertical and horizontal control joints; and
    2. wall junctions; and
    3. windows or doors; and
    4. electrical boxes; and
    5. balcony drainage and parapet flashings; and
    6. footer and header termination systems; and
  2. for a cavity wall—
    1. a transparent material for a proportion of the internal wall lining (to provide an unobstructed view of the external wall cladding) with sufficient structural capability and similar air tightness to resist the applied wind pressures; and
    2. a 15 mm diameter hole in the internal wall lining below a window.

(4) The test procedure for a direct fix cladding wall or unique wall must be as follows:

  1. Apply 100% positive and negative serviceability wind pressures to the external face of the test specimen for a period of not less than 1 minute each.
  2. Apply static pressure of either 300 Pa or 30% serviceability wind pressure, whichever is higher, in accordance with the water penetration test procedure at clause 8.5.2 of AS/NZS 4284.
  3. Apply cyclic pressure in accordance with—
    1. the three stages of Table F3V1b; and
    2. the water penetration test procedure at clause 8.6.2 of AS/NZS 4284.

(5) The test procedure for a cavity wall must be as follows:

  1. Apply 100% positive and negative serviceability wind pressures to the external face of the test specimen for a period of not less than 1 minute each.
  2. Apply static pressure of either 300 Pa or 30% serviceability wind pressure, whichever is higher, in accordance with the water penetration test procedure at clause 8.5.2 of AS/NZS 4284.
  3. Apply cyclic pressure in accordance with—
    1. stage 3 of Table F3V1b; and
    2. the water penetration test procedure at clause 8.6.2 of AS/NZS 4284.
  4. To simulate the failure of the primary weather-defence or sealing, the following procedure must be applied to the test specimen:
    1. Insert 6 mm diameter holes through the external face of the cavity wall in all places specified below:
      1. Wall/window or wall/door junctions at ¾ height.
      2. Immediately above the head flashing.
      3. Through external sealing of the horizontal and vertical joints.
      4. Above any other penetration detail not covered by (A) to (C).
    2. Repeat the static and cyclic pressure tests of (b) and (c).
    3. Within 30 minutes of the completion of (ii), remove the internal lining of the cavity wall and check for compliance with (6).
    4. With the internal lining removed, apply a final static pressure test at 50 Pa for a period of 15 minutes.

(6) Compliance is determined as follows:

  1. A direct fix cladding wall and unique wall are verified for compliance with F3P1 if there is no presence of water on the inside surface of the facade.
  2. A cavity wall is verified for compliance with F3P1 if there is no presence of water on the removed surface of the cavity, except that during the simulation of the failure of the primary weather-defence or sealing, water may—
    1. transfer to the removed surface of the cavity due to the introduced defects (6 mm holes); and
    2. contact, but not pool on, battens and other cavity surfaces.

(7) The test report must include the following information:

  1. Name and address of the person supervising the test.
  2. Test report number.
  3. Date of the test.
  4. Cladding manufacturer’s name and address.
  5. Construction details of the test specimen, including a description, and drawings and details of the components, showing modifications, if any.
  6. Test sequence with the pressures used in all tests.
  7. For each of the static and cyclic pressure tests, full details of all leakages, including position, extent and timing.
Table F3V1a Risk factors and scores
Risk factor Category Risk severity Score
Wind region Region A0-5 (AS/NZS 1170.2) Low to medium 0
Region B1-2 (AS/NZS 1170.2)
Region C (AS/NZS 1170.2) High 1
Region D (AS/NZS 1170.2) Very high 2
Number of storeys One storey Low 0
Two storeys in part Medium 1
Two storeys High 2
More than two storeys Very high 4
Roof/wall junctions Roof-to-wall junctions fully protected Low 0
Roof-to-wall junctions partially exposed Medium 1
Roof-to-wall junctions fully exposed High 3
Roof elements finishing within the boundaries formed by the external walls Very high 5
Eaves width More than 600 mm for single storey Low 0
451-600 mm for single storey Medium 1
More than 600 mm for two storey
101-450 mm for single storey High 2
451-600 mm for two storey
More than 600 mm for above two storey
0-100 mm for single storey Very high 5
0-450 mm for two storey
Less than 600 mm for above two storey
Envelope complexity Simple shape with single cladding type Low 0
Complex shape with not more than two cladding types Medium 1
Complex shape with more than two cladding types High 3
As for high risk but with fully exposed roof-to-wall junctions Very high 6
Decks, porches and balconies None Low 0
Timber slat deck or porch at ground level
Fully covered in plan view by roof Medium 2
Timber slat deck attached at first or second floor level
Balcony exposed in plan view at first floor level High 4
Balcony cantilevered at first floor level
Balcony exposed in plan view at second floor level or above Very high 6
Balcony cantilevered at second floor level or above
Table Notes
  1. Eaves width is measured horizontally from the external face of any wall cladding to the outer edge of any overhang, including fascia and external gutters.
  2. Barriers to prevent falling and parapets are considered as 0 mm eaves.
Table F3V1b Cyclic pressure
Stage number Serviceability wind pressure (%)
Min Max
1 15 30
2 20 40
3 30 60

Deemed-to-Satisfy Provisions

(1) Where a Deemed-to-Satisfy Solution is proposed, Performance Requirement F3P1 is satisfied by complying with F3D2 to F3D5.

(2) Where a Performance Solution is proposed, the relevant Performance Requirements must be determined in accordance with A2G2(3) and A2G4(3) as applicable.

A roof must be covered with—

  1. roof tiles complying with AS 2049, fixed in accordance with AS 2050; or
  2. metal sheet roofing complying with AS 1562.1; or
  3. plastic sheet roofing designed and installed in accordance with AS 1562.3; or
  4. terracotta, fibre-cement and timber slates and shingles designed and installed in accordance with AS 4597, except in cyclonic areas; or
  5. an external waterproofing membrane complying with F1D5.

Sarking-type material used for weatherproofing of roofs and walls must comply with AS 4200.1 and AS 4200.2.

(1) Subject to (2) and (3), the following glazed assemblies in an external wall, must comply with AS 2047 requirements for resistance to water penetration:

  1. Windows.
  2. Sliding and swinging glazed doors with a frame, including French and bi-fold doors with a frame.
  3. Adjustable louvres.
  4. Shopfronts.
  5. Window walls with one piece framing.

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

  1. A Class 7 or 8 building where in the particular case there is no necessity for compliance.
  2. A garage, tool shed, sanitary compartment, or the like, forming part of a building used for other purposes, except where the construction of the garage, tool shed, sanitary compartment or the like contributes to the weatherproofing of the other part of the building.
  3. An open spectator stand or open-deck carpark.

(3) The following glazed assemblies need not comply with (1):

  1. All glazed assemblies not in an external wall.
  2. Revolving doors.
  3. Fixed louvres.
  4. Skylights, roof lights and windows in other than the vertical plane.
  5. Sliding and swinging glazed doors without a frame.
  6. Windows constructed on site and architectural one-off windows, which are not design tested in accordance with AS 2047.
  7. Second-hand windows, re-used windows and recycled windows.
  8. Heritage windows.

(1) External wall cladding must comply with one or a combination of the following:

  1. Masonry, including masonry veneer, unreinforced and reinforced masonry: AS 3700.
  2. Autoclaved aerated concrete: AS 5146.3.
  3. Metal wall cladding: AS 1562.1.

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

  1. A Class 7 or 8 building where in the particular case there is no necessity for compliance.
  2. A garage, tool shed, sanitary compartment, or the like, forming part of a building used for other purposes, except where the construction of the garage, tool shed, sanitary compartment or the like contributes to the weatherproofing of another part of the building that is required to be weatherproofed.
  3. An open spectator stand or open deck carpark.