SYSTEMS 324 INSTALLATION 325 DETAILS 328

3.6.2 Fire Rated Vertical
Laminated Duct

SYSTEMS 324

INSTALLATION 325
325
General Requirements
Maximum height and 325
width dimensions 325
Plasterboard Layout 326
Plasterboard Fixing
328
CONSTRUCTION
DETAILS

INTRODUCTION Laminated duct systems are suitable Unless otherwise stated, laminated
for use with fire rated penetrations duct systems are non-load bearing
Laminated duct systems including access panels, cable trays and must not support roof, ceiling
are fire rated laminated and power points. They cannot or floor loads.
plasterboard enclosures be used for services containing
for building services. They combustible liquids or gases.
are designed to provide
fire and acoustic isolation Laminated ducts can form one up to
for electrical, plumbing four sides of a fire rated enclosure.
and air-handling services. They can be easily joined to other
The laminated duct systems plasterboard, masonry or concrete
are constructed from three walls with an equivalent or higher
layers of either 13mm or fire rating.
16mm FireShield and metal
angle framing.

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KLVD1-KLVD2

FRAME: 25x50mm or 50x50mm, x 0.7mm BMT steel angles

DUCT LINING: 3 layers of 13mm or 16mm FireShield laminated together

[13mm FireShield can be substituted with 13mm MultiShield or 13mm ImpactShield

or 13mm QuadShield]

[16mm FireShield can be substituted with 16mm MultiShield]

[Laminated Vertical Duct can be 1, 2, 3 or 4 sided]

SYSTEMS 3.6.2 Fire Rated Vertical Laminated Duct [Refer to ‘Framing’ for Maximum Height and Maximum Width dimensions]

FRL System Plasterboard Lining Plasterboard Thickness Acoustics
(Minutes) (mm) Rw (Rw + Ctr)

– /90/90 KLVD1 3 layers of 13mm FireShield 39 37 (34)

rated from both sides 38 (35)

Fire Report
FR 2340
97/1037
97/1104
98/1341
FAR 1660

– /120/120 KLVD2 3 layers of 16mm FireShield 48

rated from both sides

Fire Report
FR 2340
97/1037
97/1104
98/1341
FAR 1660

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GENERAL REQUIREMENTS Fire
Rated
Only joint the face layer. As a minimum to achieve the FRL, only use paper tape and:
Two coats of MastaBase/MastaLongset, or ✔
Three coats of MastaLite.
✔
Never joint sheets with fire sealant. [Refer to section 4] ✔
Use approved fire rated penetration details. Fire penetrations may require fire collars or other devices
to maintain fire performance.
Use fire sealant on all gaps and around perimeter, vermiculite plaster is not permitted.

For acceptable modifications or variations INSTALLATION 3.6.2 Fire Rated Vertical Laminated Duct
to fire rated systems. [Refer To Section 2.3
Fire Resistance]

MAXIMUM HEIGHT AND WIDTH DIMENSIONS Max Duct Height (m)
3.0
Max Duct Width (m) 3.6
Unlimited 4.2
3.0 4.8
2.4 5.4
1.8
1.2

1 Dimensions apply to both KLVD1 and KLVD2 systems

PLASTERBOARD LAYOUT

Vertical Layout Fire
Stagger butt joints by 600mm minimum on adjoining sheets and between layers. Rated
First layer butt joints must be backed by a steel angle of minimum 50mm width.
Stagger recessed edges by 300mm minimum between layers. ✔
✔
✔

Minimise butt joints by using long sheets.

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1st layer 25x50mm or 50x50mm, x 0.7mm
2nd layer BMT angle frame before 1st layer

3 layers of FireShield
laminated together to create
duct walls

INSTALLATION 3.6.2 Fire Rated Vertical Laminated Duct 3rd layer 25x50mm or 50x50mm, x 0.7mm
BMT angle frame after 1st layer
and before 2nd layer

FIGURE 1 Framing and Plasterboard Layout Fire
Rated
PLASTERBOARD FIXING
✔
Use the ‘Screw Only Method’. Stud adhesive is not permitted. ✔
Drive screws to just below the sheet surface, taking care not to break the paper linerboard. ✔
Laminating screws can be used to fix butt joints in the second and third layer.

SCREW TYPE AND MINIMUM SIZE FOR THE INSTALLATION OF PLASTERBOARD
TO STEEL FURRING CHANNEL

Plasterboard Thickness 1st Layer 2nd Layer 3rd Layer
60mm – 6g S screw*
13mm 25mm – 6g S screw 40mm – 6g S screw* 65mm – 6g S screw*

16mm 30mm – 6g S screw 45mm – 6g S screw*

For steel up to 0.8mm BMT use Type ‘S’ fine thread needle point screws.
For steel 0.8mm to 2.0mm BMT use Type ‘S’ fine thread drill point screws.
*40mm –10g Laminating screws may be used as detailed in installation diagrams.

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FIGURE 2 Steel Angle Frames and 1st Layer Fixing Screw Only Method

Frame 1 Steel Angle 25x50 or 50x50mm x 0.7mm
Frame 2 BMT. Installed before 1st layer
Steel Angle 25x50 or 50x50mm x 0.7mm
BMT. Installed between 1st and 2nd layers.

600mm max Sheet Layout 1st, 2nd and 3rd layers: All Vertical

Fasteners Perimeter screws 10-15mm from sheet edges.

25x50mm or 50x50mm x 0.7mm Sheet Perimeter Screw fix to steel angle at 400mm max centres
BMT angle frame before 1st layer. vertically and 600mm max horizontally.
Fix to floor and wall at 600mm max
centres and 100mm max from ends Field 2nd layer: Laminate to 1st layer at 400mm
max centres vertically and horizontally.
1st layer
3rd layer: Laminate to 2nd layer at 400mm
max centres vertically and horizontally.

400mm max Recessed Edges 1st layer: Once 2nd layer is installed, support
the recessed edge in the 1st layer with an
additional line of laminating screws through
25x50mm or 50x50mm x 0.7mm BMT 2nd layer at 400mm max centres. Stagger
angle frame after 1st layer and before recessed edges by 300mm min between layers.
2nd layer. Fix to floor and wall at 600mm
max centres and 100mm max from ends 2nd layer: Laminate to 1st layer at 400mm max
centres.

3rd layer: Laminate to 2nd layer at 400mm INSTALLATION 3.6.2 Fire Rated Vertical Laminated Duct
max centres.

Butt Joints 1st layer: Fix at 200mm max centres to
additional horizontal steel angle. Stagger butt
600mm max joints by 600mm min on adjoining sheets

and between layers.

2nd layer: Laminate to 1st layer at 200mm
max centres.

3rd layer: Laminate to 2nd layer at 200mm
max centres

Internal and All layers: Fix to angle at 400mm max
External corners centres vertically

Fire Sealant Use fire sealant on all gaps and around
perimeter to maintain fire and acoustic
integrity. [Refer to Construction Details]

Jointing Face As a minimum, only use paper tape
Layer with either two coats of MastaBase /
MastaLongset or three coats of MastaLite.
FIGURE 3 2nd and 3rd Layers [Refer to Section 4]

Stagger recessed Recessed edge in 1st layer Floating butt joints fixed to
edges by 300mm min supported by an additional line previous layer at 200mm max
between layers of laminating screws through 2nd centres using laminating screws
layer at 400mm max centres

600mm
max

400mm max 2nd layer 400mm max

400mm max 400mm
max
3rd layer
400mm
max

600mm max

10-15mm

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FIRE RATED

LAMINATED VERTICAL DUCT

Screws fixed 10mm clearance to 22mm IBS 15mm clearance
through angle plasterboard Backing Rod to plasterboard

25x50mm 0.7mm BMT steel Fire sealant required Laminating screws Fire sealant required
angle fixed to slab at 600mm to maintain fire and 50mm from sheet top. to maintain fire and
max centres and 100mm max acoustic integrity Do not fix through angle acoustic integrity
from angle ends

FIGURE 4 Laminated Duct Head to Slab FIGURE 5 Laminated Duct Deflection Head to Slab
Elevation Elevation

CONSTRUCTION DETAILS 3.6.2 Fire Rated Vertical Laminated Duct Screws fixed FireShield Small bead of fire sealant under
through angle angle filling any gaps
Small bead of fire sealant
Suitable masonry under angle filling any gaps Screws fixed through angle
fasteners
5-10mm clearance Laminating screws
to plasterboard
5-10mm clearance
to plasterboard

Suitable masonry fasteners at 600mm max
centres and 100mm max from angle ends

FIGURE 6 Laminated Duct Base to Slab FIGURE 7 Laminated Duct to Masonry Wall
Elevation Plan view

25x50mm 0.7mm BMT steel angle 25x50mm 0.7mm BMT steel angle Laminating screws
before 1st layer before 1st layer and between 1st
and 2nd layers Overlap sheet
50x50mm 0.7mm BMT steel angle edges at corners
between 1st and 2nd layers Screws fixed
through angle
Laminating screws
Set external corner bead
FIGURE 8 Laminated Duct Internal Corner
Plan view FIGURE 9 Laminated Duct External Corner
Plan view

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FIRE RATED Stagger recessed edges by
600mm min between layers
LAMINATED VERTICAL DUCT
Laminate recessed edges
Laminate recessed edges in 1st in 2nd and 3rd layer at
layer through 2nd layer at 400mm max centres
400mm max centres
FIGURE 11 Laminated Duct Recessed
FIGURE 10 Laminated Duct Recessed Edge in 2nd and 3rd Layer
Edge in 1st Layer Plan view
Plan view

Stagger butt joints by Additional 25x50mm x
600mm min on adjacent 0.7mm BMT angle to
sheets and between layers support butt joint in 1st layer

Laminate butt joints in 2nd CONSTRUCTION DETAILS 3.6.2 Fire Rated Vertical Laminated Duct
and 3rd layer at 200mm
max centres

FIGURE 12 Laminated Duct Butt Joint FIGURE 13 Laminated Duct Butt Joint
in 2nd and 3rd Layer in 1st Layer

39 - 48mm 39 - 48mm
Fire sealant
Cable tray Maximum opening size 70mm
Cable/s high and 440mm wide. Metal pipe

Check max opening

Fire sealant

FIGURE 14 Typical Cable Tray Penetration FIGURE 15 Typical Metal Pipe Penetration
Up to 2 hours FRL Up to 2 hours FRL
Example Only Example Only

39 - 48mm

Promat Promaseal 20mm max gap between
fire sealant fire collar and FireShield

Plastic pipe

Promat type FCW fire collar.
Check sizing with Promat.

FIGURE 16 Typical Fire Collar Penetration
Up to 2 Hours FRL

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