CEMP-E
TI 809-07
NOVEMBER 1998
and constructed so that all water entering the cavity is directed out through weep holes. Ends
and sill flashing must be lapped and sealed at joints. Ends will be turned up at sills and heads.
Flashing must also be turned up behind the moisture barrier a minimum of 152 mm (6") and will
be attached to the sheathing. Flashing must extend to the exterior face of the masonry wall.
Weep holes as described herein will be provided.
i. Shelf Angles. Shelf angles will be hot-dipped galvanized structural steel members.
Angles will be provided in segments, approximately 3.1 m (10 `) in length, with gaps between
segments. Shelf angles will be detailed to allow enough gaps for thermal expansion and
contraction of the steel in angle runs and at building corners. Corners of buildings will have
corner pieces with each leg no less than four 1.2 m (4 ') in length where possible. Any areas that
are welded will be touched-up with a zinc-rich paint.
j. Cavity. A cavity space of 51 to 102 mm (2 to 4 ") will be provided between the
masonry veneer and the exterior sheathing or, if insulation is used over the sheathing, between
the masonry veneer and the insulation. In all situations a 51 mm (2 ") minimum wide air space is
required and needs to be coordinated with the standard dimensions of lintels and shelf angles.
The cavity provides water drainage and prevents moisture migration from the masonry wythe to
the steel stud backup wall. The cavity should be kept clean of mortar droppings. To keep mortar
droppings from plugging the weep holes place a course gravel or drainage material behind the
weep holes in the cavity to a minimum depth of 102 mm (4").
k. Masonry Crack Control. Crack control will be in accordance with the Masonry Manual
for anchored veneer.
l. Weep Holes. Head joint weep holes that extend through the masonry wythe will be
provided immediately above the mortar bed joint containing the horizontal leg of the through wall
metal flashing and near the top of the wall at the same spacing. Details along with the required
spacing will be shown on a wall section on the contract drawings. Weep holes need to be kept
free of debris during construction and need to be functional at the end of the construction period.
m. Head Joint Vents. Head joint vents will be placed near the top of the veneer wythe at
the same spacing as the weep holes. These vents will help maintain a dry cavity.
4. WALL SYSTEM DESIGN REQUIREMENTS. This exterior wall system will be designed
assuming that all out-of-plane lateral loads are resisted entirely by the steel stud backup wall.
The veneer anchors will be designed to transfer those lateral loads to the steel studs. All in-plane
loads will be isolated from the stud wall system. All vertical masonry loads will be carried by a
shelf angle or the foundation wall. Veneer anchorage will provide sufficient movement to account
for the story drift displacements around window and door openings.
a. Steel Studs. Studs will be sized and spaced to resist wind or seismic loads. Wind
loads on steel studs and framing will be in accordance with EI 01S901 and seismic loads will be
in accordance with TI 809-04. Supplemental framing will be added at the heads, jambs and sills
of openings, as required by design, to resist the tributary loads from the opening closures (doors,
windows, etc.). The stud system selected for lateral loading will be checked for deflection, which
normally controls panel wall design. Material thickness for the top and bottom runners will be
designed for allowable stress and deflection and will be equal to or thicker than the steel stud
used in the wall. The minimum delivered material thickness for steel studs is shown in table 1-1.
(1) Section properties. All section properties needed for the design of the steel
studs and framing will be in accordance with AISI.
(2) Allowable stresses. All allowable stresses used for the design of the steel
studs and framing will be in accordance with AISI.
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