minimum of 150 mm 6 inch. Openings shall be properly flashed. [All joints,
seams and penetrations shall be sealed with compatible silicone sealant.]
3.2.12
Floating Interior Angles
Locate the attachment fasteners adjacent to ceiling and wall intersections
in accordance with ASTM C 840, System XII or GA 216, for [single-ply] [and]
[two-ply] applications of gypsum board to wood framing.
3.2.13
Control Joints
Install expansion and contraction joints in ceilings and walls in
accordance with ASTM C 840, System XIII or GA 216, unless indicated
otherwise. Control joints between studs in fire-rated construction shall
be filled with firesafing insulation to match the fire-rating of
construction.
3.2.14
Application of Foil-Backed Gypsum Board
Apply foil-backed gypsum board in accordance with ASTM C 840, System XIV or
GA 216.
3.2.15
Application of Predecorated Gypsum Board
Apply predecorated gypsum board in accordance with GA 224. Attach
predecorated gypsum board with adhesive and fasteners as recommended by the
manufacturer. Conceal fasteners in the finished work.
3.2.16
Application of Impact Resistant Gypsum Board
Apply in accordance with applicable system of ASTM C 840 as specified or GA
216. Follow manufacturers written instructions on how to cut, drill and
attach board.
3.3
APPLICATION OF CEMENTITIOUS BACKER UNITS
3.3.1
Application
In wet areas (tubs, shower enclosures, saunas, steam rooms, gang shower
rooms), apply cementitious backer units in accordance with ANSI A108.11. A
15 lb7.6 kg asphalt impregnated, continuous felt paper membrane shall be
placed behind cementitious backer units, between backer units and studs or
base layer of gypsum board. Membrane shall be placed with a minimum 6 inch
150 mm overlap of sheets laid shingle style.
3.3.2
Joint Treatment
ANSI A108.11.
3.4
FINISHING OF GYPSUM BOARD
Tape and finish gypsum board in accordance with ASTM C 840, GA 214 and GA
216. Plenum areas above ceilings shall be finished to Level 1 in
accordance with GA 214. Water resistant gypsum backing board, ASTM C 630/C
630M, to receive ceramic tile shall be finished to Level 2 in accordance
with GA 214. Walls and ceilings to receive a heavy-grade wall covering or
heave textured finish before painting shall be finished to Level 3 in
accordance with GA 214. Walls and ceilings without critical lighting to
receive flat paints, light textures, or wall coverings shall be finished to
SECTION 09250
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