9 - Ceilings, Partitions and Access Floors
9 - Ceilings, Partitions and Access Floors
9 - Ceilings, Partitions and Access Floors
CORNICES
Material and fixing
Cornices must be 75 mm wide coved gypsum cornice to comply with SABS 622, or 6 mm thick coved
fibre cement cornice with inside and outside corner pieces, or foam moulded, hardwood or softwood
cornices, to profile as specified.
Nail cornices to brandering with 38 mm galvanised clout nails at 300 mm maximum centres.
Nail cornices to walls with 38 mm hardened steel nails, or glue gypsum or fibre-cement cornices to walls
with approved contact adhesive or 3-4 mm gypsum plaster.
Mitre corner joints, splay all heading joints. Join fibre-cement cornices with shaped metal H-profile jointing
strips.
CEILING INSULATION
Mineral fibre insulation
Insulation must be mineral fibre blanket or batts insulation to comply with SABS 1381 part 1, or cellulose
loose fill thermal insulation to comply with SABS 1381 part 6, as specified.
Lay insulation over ceiling to thickness or depth as specified.
Fit blankets or batts snugly between roof trusses. Nail batts where necessary.
Reflective foil laminates insulation
Reflective foil laminates must comply with SABS 1381 part 4, class A (reinforced, with one side or both
sides reflective as specified).
Lay foil on galvanised or PVC-coated span wires at recommended centres, and with 140 mm laps so that
span wires support each lap. Draw foil tight and fix to bottom and top purlin by gluing, double-sided tape,
or sheet steel straps pop-riveted to the purlin, all according to manufacturer’s instructions.
CEILING HATCH
Timber hatch
Trim 650 x 650 mm minimum clear opening in ceiling with 38 x 100 sawn softwood trimmers spiked to
beams or trusses.
Form hatch frame of brandering as for ceiling.
Form trap door of brandering and ceiling board as for ceiling.
Hang trap door with one pair 75 mm steel hinges screwed to frame, so that trap door can open 180
degrees on to top of ceiling brandering.
Provide 50 x 19 mm hardwood fillets nailed or screwed to ceiling around hatch opening, to carry trap door
in closed position. Mitre corners of fillets.
Steel hatch
Approved 0,6 mm pressed steel ceiling trap door, hinged to open 180 degrees onto ceiling, in 25 x 25 x
3 mm T-profile steel frame. Clear opening must be at least 650 x 650 mm.Drill frame twelve times and
screw onto ceiling brandering.
DRYWALL PARTITIONS
Plasterboard
Plasterboard must be standard grade plasterboard to comply with SABS 266. If specified, board must be
covered with paper backed vinyl of specified weight in grams per m 2.
Studs and tracks
Studs and tracks must be 51 or 63,5 x 0,5 mm thick galvanised steel.
Aluminium extrusions
Extruded aluminium sections must be alloy 6063 or 6261 in temper T5 or T6. If specified, anodising must
be in strict accordance with SABS 1247, and powder coating must be by applicators approved by the
specified powder manufacturers, and in accordance with SABS 1247.
Glass
Glass must be as specified. Provide a warranty from the manufacturer against delamination and colour
degradation for a period of at least five (5) years.
Installation
Install drywall partitions strictly according to the material manufacturer's instructions.
Partitions must conform to the specified fire ratings.
Partitions must conform to the appropriate deflection requirements as laid down by the South African
Building Interior Systems Association (SABISA).