Rolling grill shutter is meant to provide visibility or ventilation or both, the degree of protection and

safety is less as compared to a rolling shutter. The situations where a certain amount of ventilation

combined with safety is required rolling shutter-cum-grill may be provided in which the rolling shutte

may have a rolling grill portion either at the top or at the bottom or at both places. In addition, the rolling grill portion may also be provided in the middle of the shutter. The total height of the grill portion in all the

segments of rolling shutter-cum-grill shall not exceed 1.0 m and the height of the grill portion in any

individual segment shall not be more than 0.5 m.

The shutter be built up of inter locking lath section formed from cold rolled steel strips.

The thickness of the sheets from which the lath sections have been rolled shall be not less than 0.90

mm for the shutters upto 3.5 m width. Shutters above 9 metres width should be divided in 2 parts with

provision of one middle fixed or movable guide channel or supported from the back side to resist wind

pressure. The lath section shall be rolled so as to have interlocking curls at both edges and a deep

corrugation at the centre with a bridge depth of not less than 12 mm to provide sufficient curtain of

stiffness for resisting manual pressures and normal wind pressure. Each lath section shall be continuous

single piece without any welded joint. When interlocked, the lath sections shall have a distance of 75

mm rolling centers. Each alternate lath section shall be fitted with malleable cast iron or mild steel clips

securely riveted at either ends, thus locking in the lath section at both ends preventing lateral movement

of the individual lath sections. The clips shall be so designed as to fit the contour of the lath sections