Suspended Grid
90/90/90
LB
FIRE RATED FLOOR/CEILING SYSTEMS – SECTION 3.2
Suspended Grid
JANUARY 2006
SPECIFICATION
NUMBER
LOADBEARING
CAPACITY
FIRE RESISTANCE RATING
LINING REQUIREMENTS
STC
IIC
SYSTEM WEIGHT
APPROX
GBSC 90
LB
90/90/90
1 layer 13mm
GIB Fyreline® + 1 layer
of 16mm GIB Fyreline®
53
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64kg/m2
CEILING LINING
FLOOR FRAMING
Timber floor joists complying with NZS 3604 spaced at
600mm centres maximum.
Alternatively, a proprietary I-joist system may be used subject
to specific structural design and approval by the normal
building consent process.
FLOORING
Minimum flooring shall be nominal 20mm thick particle board
or minimum 18mm thick structural plywood fixed to joists in
accordance with the manufacturers specifications.
Note: If tongue and groove sheet flooring is used, verification
of performance must be obtained from the supplier of the
flooring system.
1 layer of 13mm GIB Fyreline® shall be fixed parallel to the
DGL55D main tees and positioned so tapered edges are
located on the main tee. Sheet end butt joints must occur
on DGW40D-1200 cross tees.
One layer of 16mm GIB Fyreline® shall be fixed parallel to
main tees but offset by 600mm in both directions. Sheet end
butt joints must occur on DGW40D-1200 cross tees.
Sheets shall be touch fitted.
FASTENING THE LINING
Fasteners
INNER LAYER:
25mm x 6g GIB® Grabber® Drywall Self Tapping
Screws.
OUTER LAYER: 41mm
SUSPENSION SYSTEM
USG Drywall Grid Suspension System comprising 2.5mm
wire hangers or DJ4040 wall angles at 1200mm centres
maximum. Hangers support DGW55D main tee at 1200mm
centres maximum. DGW40D-1200 cross tees installed at
600mm centres.
The distance between the underside of the flooring and the
top of the ceiling linings shall be a minimum of 450mm.
x 6g and 38mm x 10g Laminator screws
as above.
Fastener Centres
INNER LAYER: 150mm centres around perimeter of each sheet.
Single screws at 200mm centres along each DGW40D-1200
cross tee.
OUTER LAYER: As above. Where sheet perimeter fasteners do
not coincide with steel suspension component, GIB® Grabber®
Laminator screws are to be used.
Place fasteners 12mm from sheet edges.
Note 1: Additional DGW40D-1200 cross tees are required 200mm both sides
of sheet end butt joints.
WALL/CEILING JUNCTIONS
manufacturer’s specification.
JOINTING
Unstopped.
OUTER LAYER: All fastener heads stopped and all
sheet joints tape reinforced and stopped in
accordance with the publication entitled
“GIB® Site Guide”.
INNER LAYER:
The internal angle between the ceiling and walls must be
protected by GIB-Cove® adhered with GIB-Cove® Bond,
or boxed corners (square stopped) filled and taped in
accordance with the publication entitled “GIB® Site Guide”.
20mm Particle board floor
Joists at 600mm centres maximum
USG Drywall Grid
Suspension System
150mm
600mm
Single screws at 200mm centres along
main tee and 1200mm cross tee
Perimeter fixing at
150mm centres both layers
150mm
In order for GIB® systems to perform as tested, all components must be installed exactly as prescribed. Substituting components
produces an entirely different system and may seriously compromise performance. Follow system specifications.
FOR FURTHER INFORMATION VISIT WWW.GIB.CO.NZ AND SEARCH SPECIFICATION CODES: GBSC 90. ISSUE DATE: JANUARY 2006
GIB® FIRE RATED SYSTEMS
Note 2: Suspension system must be installed in accordance with
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