Method of measurement of building and civil engineering works, Part 9: roof covering (including cladding)
1973 Edition

The standard IS 1200 Part 9 (1973) establishes a uniform approach to measuring roof coverings, including cladding, for both buildings and civil engineering projects. Measurements are generally taken based on the area of the installed covering, incorporating overlaps and laps, and expressed in square meters (m²). The process includes all fixed roofing materials like tiles, metal sheets, and cladding panels. Measurements are rounded off following IS 2-1960 rules to maintain consistency. The plan area is measured including overlaps, with deductions made for openings such as skylights only when specified.

According to IS 1200 Part 9, laps along ridges, hips, valleys, and flashings are not measured separately; they are included within the total length or area measurement. The roof sheeting area is measured flat, without deductions for corrugations or laps. Although laps and fixing methods must be described in the specifications, they are not accounted for separately in quantities to avoid double counting.

Per IS 1200 Part 9, openings larger than 0.4 square meters must be deducted from the total roof covering area. Openings of 0.4 square meters or less are not deducted but should be counted in number. The length of cuttings made to accommodate these openings is measured in running meters. Overlaps at ridges, hips, and other features are included as part of the roof measurement and are not deducted separately.

Yes. IS 1200 Part 9 requires that accessories like ridge tiles, ridge finials, and ventilators be measured and enumerated individually. Additional fittings such as drop ends, stop ends, nozzles, and angles are measured as extras over the length of gutters or pipes. Other items like eaves fillers, aprons, barge boards, flashings, and louvers are measured in running meters, including laps and fixing details. Measurement of ridges, hips, and valleys is done along the centerline in running meters, with girth and flashings measured in square meters.

Bills of quantities should comprehensively describe the roofing materials, including the type (e.g., Nainital pattern sheeting), quality, and all associated accessories such as rolls and clips. Measurements should be based on the flat surface area, excluding girth. Waterproofing treatments must be detailed with type, quality, quantity, and laps. All cutting, waste, openings, wedging, and pointing at masonry edges must be accounted for. Turn-ups and turn-downs at eaves, verges, and abutments are included in the waterproofing measurements. Quantities are expressed in square meters, ensuring clarity and accuracy for costing and execution.