This standard outlines detailed procedures for on-site application of waterproofing and damp-proofing using glass fibre tissue reinforced bitumen. It specifies the material requirements, surface preparation protocols, installation techniques, and layering schemes for roofs, basements, and subterranean structures. It is a crucial reference for professionals ensuring effective moisture resistance in civil engineering projects.
Overview
This standard outlines detailed procedures for on-site application of waterproofing and damp-proofing using glass fibre tissue reinforced bitumen. It specifies the material requirements, surface preparation protocols, installation techniques, and layering schemes for roofs, basements, and subterranean structures. It is a crucial reference for professionals ensuring effective moisture resistance in civil engineering projects.
Audience
Contents
Structure
This section defines the extent of the code, covering the design, detailing, and preparatory tasks for moisture protection in buildings. It applies to waterproofing and damp-proofing techniques aimed at preventing water ingress into structures. Included are specifications for bitumen primers, glass fibre reinforced felts, and particular materials like industrial and paving bitumen. The use of pea-sized gravel for concrete and masonry roofs is recommended for added protection. Numerical data should be rounded according to IS 2:1960 to maintain consistency.
Clarifies key terms used within the standard, including definitions related to design and preparation for waterproofing and damp-proofing. Specifies the use of pea-sized gravel or grit for roofing applications and emphasizes the importance of rounding numerical values per IS 2:1960. Cross-references related IS codes for individual material specifications are also provided.
Outlines the procedures to prepare surfaces prior to treatment application, referencing IS 3067-1966 and IS 1609-1976 standards. Emphasizes keeping surfaces dry and free from moisture to ensure proper adhesion of bitumen and glass fibre tissues. Details the cleaning process and primer application rate (0.4 kg/m²), with instructions to allow the primer to become touch dry before subsequent coats.
Details the recommended bonding materials such as blown bitumen (IS 702-1961) and residual bitumen (IS 73-1961), including acceptable penetration values (≤ 40 as per IS 1203-1958). Discusses the use of pea-sized gravel or grit for roof protection and summarizes the bitumen types and glass fibre tissue requirements. Emphasizes adherence to rounding rules for test data.
Describes finishing methods for concrete, masonry, and metal roofs, recommending bitumen primers at 0.4 kg/m² and allowing them to dry before further treatment. Specifies suitable bitumen types and penetration limits, with heating requirements before application. Includes tables summarizing primer types, quantities, and application conditions to ensure optimal bonding and durability.
Presents detailed treatment procedures for roofs under varying rainfall intensities, defining moderate, heavy, and extra heavy duty classifications. Specifies the number of bitumen coats, glass fibre layers, and total courses required for each category. Describes the typical five-course sequence including primer, bitumen coats, glass fibre application with overlaps, and finishing with pea gravel or alternatives. Provides notes on special treatments for corrugated roofing joints.
Specifies normal, heavy, and extra heavy duty treatments for subterranean structures, detailing the number of bitumen coats and glass fibre tissue layers for each. Includes application rates (minimum 2.4 kg/m² per coat) and layering sequences with perpendicular embedding of fibre tissues. Suggests optional mastic asphalt finishes for enhanced protection and outlines precautions during backfilling to protect the waterproofing membrane.
Describes the step-by-step method for laying waterproofing treatments, including surface cleaning, priming, application of hot bitumen and embedding glass fibre tissue with appropriate overlaps, and the layering sequence. Provides guidelines for staggering joints and embedding finishing materials like pea gravel into hot bitumen. Includes tables showing treatment types, number of coats, layers, and finishing details tailored to rainfall severity.
Outlines the method for damp-proofing application including surface preparation, priming, and layering of bitumen coats with glass fibre tissues. Specifies coat rates, overlaps, and perpendicular embedding for different duty levels. Details optional protective finishes such as mastic asphalt and highlights the importance of protecting basement walls during backfilling.
Lists essential equipment for applying the in-situ glass fibre reinforced bitumen treatments, including bitumen melting kettles with agitators, rubber squeegees for even spreading, spraying and watering cans for surface preparation, and auxiliary items like mineral turpentine and scaffolding. Summarizes specifications for treatment application rates, overlaps, layer arrangements, and finishing practices to ensure quality and durability.
Frequently Asked
As per IS 9918 (Clause 4.2), the glass fibre tissue must be a thin, flexible, chemically resistant borosilicate glass fibre mat bonded with thermosetting phenolic resin, featuring a random open porous structure. The minimum specified weight is 40 grams per square meter, with a nominal thickness of 0.50 ± 0.1 mm, complying with the physical property requirements detailed in IS 7193-1974 Appendix A. These specifications ensure the material's durability and effectiveness when embedded in bitumen membranes.
IS 9918 recommends using blown bitumen conforming to IS 702-1961 or residual bitumen per IS 73-1961, or a blend of both for bonding purposes. The bitumen penetration value should not exceed 40 dmm, based on IS 1203-1958 testing. Bitumen must be heated to the appropriate working temperature before application. For waterproofing media, suitable bituminous compounds that embed glass fibre reinforcement to form a continuous moisture barrier are specified.
Surfaces should be thoroughly cleaned to remove dirt, oil, grease, loose particles, and contaminants. Any old or deteriorated surfaces must be repaired or renewed using cement mortar or lime-surkhi mortar. The surface must be kept dry and free from moisture. A bitumen primer is applied at 0.4 kg/m² and allowed to become touch dry before proceeding. Ensuring dry walls is also crucial for proper adhesion and impregnation of glass fibre tissue.
The distinctions lie in the number of bitumen coats, glass fibre tissue layers, and total treatment courses. Normal duty involves 2 bitumen coats with 1 glass fibre layer and 5-6 total courses, suitable for moderate rainfall. Heavy duty adds an extra bitumen coat and a second glass fibre layer embedded perpendicularly, totaling 7-8 courses, appropriate for severe rainfall conditions. Extra heavy duty further increases to 4 bitumen coats and 3 glass fibre layers with perpendicular orientation, totaling 9-10 courses, designed for very severe rainfall scenarios.
For basement waterproofing, normal duty requires 2 layers of glass fibre tissue with 3 bitumen coats, totaling 6 courses. Heavy duty increases to 3 glass fibre layers and 4 bitumen coats (8 courses), while extra heavy duty comprises 4 glass fibre layers and 5 bitumen coats (10 courses). Each glass fibre layer is embedded perpendicular to the previous one, with bitumen coats applied at a minimum rate of 2.4 kg/m² per coat. Optional mastic asphalt finishes can be added for extra protection.
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