Construction Details
FRL 60/60/60 Duct Protection Soffits to Unlined Ducts
• Erect framing constructed from CH studs placed horizontally at 600mm centres fitted into J-Runner framing at the ceiling edges.
• Place 25mm Boral Shaft Liner Panels between H flanges of CH studs.
• Screw attach shaft liner panels to upper flange of J-Runners with 45mm gypsum screws at 200mm centres.
• Screw attach 2 layers of 16mm Boral Firestop Plasterboard to bottom flange of CH studs & J-Runners.
• Apply bottom layers across the bottom flanges of framing staggering all joints min. 600mm.
• Screw fasten sheets at 300mm in field of board and 200mm centres on edges and ends.
FRL 90/90/90 Duct Protection Soffits to Lined and Unlined Ducts
• Erect framing constructed from CH studs placed horizontally at 600mm centres fitted into J-Runner framing at the ceiling edges.
• Place 25mm Boral Shaft Liner Panels between H flanges of CH studs.
• Screw attach shaft liner panels to upper flange of J-Runners with 45mm gypsum screws at 200mm centres.
• Screw attach 3 layers of 16mm Boral Firestop Plasterboard to bottom flange of CH studs & J-Runners.
• Apply the first two layers across the bottom flanges staggering all joints min. 600mm.
• Screw fasten sheets at 300mm in field of board and 200mm centres on edges and ends.
• Apply bottom (third) layer perpendicular to the previous layers, and screw fasten to framing at 300mm in field of board and 200mm centres on edges and ends.

FRL 120/120/120 Duct Protection Soffits to Unlined Ducts
• Erect framing constructed from CH studs placed horizontally at 600mm centres fitted into J-Runner framing at the ceiling edges.
• Place 25mm Boral Shaft Liner Panels between H flanges of CH studs.
• Screw attach shaft liner panels to upper flange of J-Runners with 45mm gypsum screws at 200mm centres.
• Screw attach 3 layers of 16mm Boral Firestop Plasterboard to bottom flange of CH studs & J-Runners.
• Apply the first two layers across the bottom flanges staggering all joints min. 600mm.
• Screw fasten sheets at 300mm in field of board and 200mm centres on edges and ends.
• Apply bottom (third) layer perpendicular to the previous layers, and screw fasten to framing at 300mm in field of board and 200mm centres on edges and ends.
• Screw fix 100mm wide cover strips of 10mm Standard Core Plasterboard over exposed top flanges of steel framing.
FRL 120/120/120 Duct Protection Soffits to Lined Ducts
Construction as for unlined ducts but without 10mm cover strips.