Summaries of Indian Standards for Building Materials
2005 Edition

The standard specifies typical brick dimensions including Modular bricks (190x90x90 mm), Modular Thin bricks (190x90x40 mm), Non-Modular bricks (230x110x70 mm), and Non-Modular Thin bricks (230x110x30 mm). Dimensional tolerances for a stack of 20 bricks are ±80 mm in length, ±40 mm in width, and ±40 mm in height depending on the brick type. Bricks should be uniform, free from cracks, with smooth faces and well-defined edges. Frogs or indentations of 10 to 20 mm depth are required for certain brick sizes. Refer to IS 6165:1992 for more detailed shapes and dimensions.

Recommended testing procedures include flexural strength tests to measure bending resistance (with a minimum bending strength of 24.5 N/mm² for pipes up to 150 mm diameter), crushing strength tests for compressive load capacity, three-edge bearing tests for drainage and sewer pipes, impact resistance tests, flattening resistance tests, stress relief tests for socket-end pipes ensuring no defects, and water absorption tests to assess durability. Detailed methods are prescribed in IS 3597:1998, and hydrostatic pressure tests are conducted according to pipe class ranging from 0.5 MPa up to 2.5 MPa.

Particle boards are categorized by density: Low Density Particle Boards have approximately 400 kg/m³ density with moisture content up to 16%, minimum modulus of rupture of 1.5 N/mm², and limited swelling after immersion. Medium Density Fibre Boards, as per IS 12406:2003, range from 600 to 900 kg/m³ and are graded into Grade I (higher performance) and Grade II (moderate). Wood wool slabs per IS 3308:1981 are classified as Type 1 (lightweight, non-structural) and Type 2 (heavy-duty, load-bearing), with uniform thickness and standard dimensions.

Manhole covers are classified by load-bearing grades: LD-2.5 (2.5 tonnes) for residential/light traffic, MD-10 (10 tonnes) for service lanes and moderate traffic, HD-20 (20 tonnes) for commercial roads and heavy vehicles, and EHD-35 (35 tonnes) for extra-heavy duty locations such as ports and industrial zones. Covers are manufactured from grey cast iron and must comply with load tests using a 300 mm diameter loading block, with permanent deformation limits specified. Selection depends on anticipated traffic load and location.

Timbers must be kiln-seasoned and treated with approved preservatives to enhance durability. Sapwood of durable species and both heartwood and sapwood of non-durable species require treatment. Leachable water-soluble preservatives are prohibited. Recommended preservatives include fixed water-soluble types such as Chromated Copper Arsenate (CCA) and Chromated Copper Boron (CCB), as well as non-leachable solvent-based preservatives according to IS 401:1982. Treatments follow pressure or soaking methods depending on timber use and exposure.