LAMBDABOARD° laminated polyisocyanurate core board with a minimum core density of 34kg/m³, minimum thickness of ____ mm; in widths of 1,220mm with a _____(Km²/W) R-Value. Finish shall be White Mineral and Mineral Natural laminated on each side. Lambdaboard to be trimmed if necessary, to fit truss centres, boards be press mechanically fastened into purlins / battens. Dry wall fasteners must be used and fixed through the board into purlins / battens, or using quarter rounds nailed into trusses, all in accordance with manufactures specification.