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(1) For masonry veneer, the clear width of a cavity between the masonry veneer and the exterior face of the supporting frame must not be—
less than 25 mm wide; and
more than 75 mm wide.
(2) For cavity masonry, the clear width of a cavity between the inner and outer masonry leaves must not be—
less than 35 mm; and
more than 75 mm.
(3) Where masonry veneer and cavity masonry in (1) and (2) are constructed on a slab-on-ground, the cavity must be drained to the outside in accordance with 5.7.5.
(4) The exterior masonry leaf must not overhang the edge of the slab by more than 15 mm.
Explanatory information
The 25 mm clear width of the cavity needs to be maintained regardless of any wall membranes, sheet bracing or services installed to the supporting frame.
Where mullions are located within a cavity, a vertical damp-proof course must be placed between the outer masonry leaf and the mullion to prevent moisture penetration.
embossed black polyethylene film of high impact resistance and low slip, with a nominal thickness of 0.5 mm prior to embossing, and comply with clause 7.6 of AS/NZS 2904; or
polyethylene coated metal, that has an aluminium core of not less than 0.1 mm thick, is coated both sides with bitumen adhesive enclosed in polyethylene film of not less than 0.1 mm thick on each face, and has a nominal total thickness of not less than 0.5 mm prior to embossing; or
bitumen impregnated materials of not less than 2.5 mm thick, that comply with clause 7.5 of AS/NZS 2904; or
termite sheet materials complying with Part 3.4 (with no penetrations) serving the purpose of a damp-proof course and/or flashing that is continuous through the wall or pier.
located so as to form a continuous damp-proofing barrier—
around the bottom perimeter of walls where constructed on a concrete slab; and
in walls and piers below suspended floors; and
where a masonry wall passes through a roof; and
where a roof abuts an external masonry wall; and
to the bottom and tops of windows and doors and the like in accordance with (3), except a damp-proof course or a flashing need not be provided to the top of a window or door where the opening is protected by an eave of a width more than 3 times the height of the masonry veneer above the opening; and
continuous through the wall or pier and be visible from the outside face of the wall.
75 mm above the finished surface level of adjacent paved, concreted or landscaped areas that slope away from the wall; or
50 mm above finished paved, concreted or landscaped areas complying with 3.3.3(b)(ii) and protected from the direct effects of the weather by a carport, verandah or the like; or
15 mm above finished paved, concreted or landscaped areas; or
0 mm above finished paved, concreted or landscaped areas if the damp-proof course is protected from the direct effects of the weather by a carport, verandah or the like.
(3) Sill and head flashings serving openings must be—
installed so that the flashing extends not less than 150 mm beyond the reveals on each side of the opening; and
located not more than—
one course below the sill brick course; and
300 mm above the opening; and
turned up in the cavity not less than 150 mm above the opening; and
(1) Except where excluded by (2), open perpend joints (weepholes) must be created in the course immediately above any flashing (including above any damp-proof course acting as a flashing) and be—
a minimum of 50 mm in height, by the width of the vertical mortar joint; and
at not more than 1.2 m centres; and
(2) Weepholes are not required in the following locations: