Technical Literature

Good Design Practice
System Performance
 Boral Plasterboard will provide test certificates for published fire, sound and structural data covering systems designed and constructed in accordance with the Company’s published specifications.

Tests are conducted on Company systems to meet performance requirements set down by regulatory authorities. System performance following substitution of materials or compromise in design cannot be certified. Failure may result under critical conditions.
Control Joints
Shaft Wall surfaces should be isolated with control joints or other means where:
• Type of construction changes within the plane of the Shaft Wall.
• Provide control joints at 9 metre maximum centres. Ceiling-height door frames may be used as control joints as may less than ceiling-height door frames if control joints extend to ceiling from both corners.
Penetrations
Penetrations of the Shaft Wall by door frames and fire dampers require additional reinforcement at corners to distribute concentrated stresses if a control joint is not used. Where access panels or large fire damper penetrations occur in shafts having pressure loads, headers, sills and adjacent channels may require reinforcing to properly distribute these loads.
Pressure Loads
Where Shaft Walls enclose lift and return air shafts, and intermittent pressures up to 700 Pa are expected, sealant is recommended to seal peripheries, at intersections with floor slabs, columns and similar abutments, at penetrations, to minimize whistling and dirt accumulation due to air movement.

Shaft Walls may be used for air handling with sustained pressures up to 500 Pa (for pressures exceeding 350Pa, refer Boral Plasterboard Sales Offices). Sealant selection, together with joint treatment, surface coatings and details to seal the wall under these sustained pressures, must be provided by the designer. When air pressure exceeds 500 Pa, the air handling should be contained within a metal duct.
Electric Boxes
Cavity Shaft Wall will accommodate outlet boxes with depths up to the studs depth.

Screws
Boral Plasterboard Needle Point Type S and Drill Point Type D screws are suitable for fixing plasterboard to 0.55mm, 0.8mm and 0.9mm B.M.T. steel studs. Boral Plasterboard Drill point Type D screws should be used for fixing plasterboard to steel up to 2mm uncoated thickness.

Screw lengths should be minimum 30mm for base layer, 45mm for face layer and at least 10mm longer than the total thickness for other applications. Boral Plasterboard Type L laminating screws should be specified for laminating plasterboard to plasterboard, as required in back blocking penetrations, closing to Jamb Struts and around doors.
Steel Frame Construction
Runners and studs fixed to beams and columns should be installed before steel is spray-fireproofed. Excess fireproofing should be removed from runners, studs, beams and columns before installing Shaft Wall Liner and applying sealant.
Steel Door Frames
Pedestrian Door
Steel door frames should be rust resistant coated and have throats accurately formed to overall thickness of the Shaft Wall plus 2.5mm minimum to 3.5mm maximum. Jamb fixing straps should be 3mm thick mild steel welded to door frame. Screw fix steel Jamb Struts to fixing straps.

Apply Boral Plasterboard Jointing Compound just before inserting face layer into frame. Do not terminate plasterboard against door frame return. Provide bracing where required by installing diagonal bracing from Jamb Struts to structure.
Lift Landing Door
Screw fix Jamb Struts to door frame. Provide bracing where required by installing diagonal bracing from Jamb Struts to structure.
Height
Where Cavity Shaft Wall height exceeds maximum available panel height, Shaft Liner Panel end joints should be positioned within the upper and lower third of wall and joints reinforced with horizontal CH Stud, cut to fit between adjacent vertical studs. Walls over 4.8 metres high should have studs screw-fixed to runners. Joints in adjacent plasterboard sheets should be staggered top and bottom to prevent a continuous horizontal joint.