GAIL (India) Limited

64The Gypsum boards used for false ceiling shall have following properties.iiiThermal Conductivity – 0 16 W / mkThermal Resistancea. For 9.5 mm thick board – 0.06 m2 K/Wb. For 12.5 mm thick board – 0.08 m2 K/Wc. For 15 mm thick board – 0.09 m2 K/WiiiFire Propagationa. Fire PropagationIndex of performance not exceeding 12 and a sub index not exceeding 6 (when each side is testedseparately to BS 476 Part – 6).b. Surface spread of flame Class 1 (both sides) as / test to BS 476 Part – 7).Gypsum boards shall be specified thickness, and of specified finish (painted / prelaminated). The Gypsumboards shall be screw fixed to the under side of false ceiling grid system with 12.5 mm dry wall screw @230 mm C/C by drilling machine. Joint in the board shall be finished flush with fillers, finisher and primeras per manufacturer’s recommendation to givea seamless finish.Necessary cut-outs for Electrical / AC and other fixtures shall be provided with a framing of wallchannels.In case of fixing on modular grid system, the boards shall be cut to required size and fixed in the samemanner as in clause 11.2.1.The finished false ceiling shall be perfectly levelled and aligned, at desired height as per drawings.1.3 PARTITION FRAME WORK:1.3.1 G.I.GI partition frame work shall consist of 0.9 mm tk, 15 x 45 x 15 mm GI channel shaped horizontalmembers and 0.5 mm th, 20 x 27 x 30 mm GI channel shaped vertical studs screwed to each other. Thechannel sections shall have 10 mm lips. Screws used shall be drywall type. Horizontal and verticalspacing shall be maximum 610mm. The perimeter of the frame work shall be bound y continuouschannel. The floor and ceiling channel shall be fixed to floor and ceiling by nylon raw plug and metallicdash fasteners respectively.In case of low height partitions, the channels shall be boxed together.The frame work arrangement shall be in accordance with the pattern for partition facing, glazing inpartition etc.1.3.2 GYPSUM PARTITION BOARDGypsum boards for partition shall be same as specified in clause No.11.2.4 and shall be fixed and finishedin the same manner as specified in clause No.11.2.4.Number of Gypsum board layers shall be as specified and with finishing (painting or pre-lamination) asspecified in the item description.