What is the minimum compressive strength required for burnt clay hollow bricks?

The minimum compressive strength is 3.5 N/mm² when calculated over the gross area.

What is the maximum permissible water absorption for these bricks?

Water absorption should not exceed 20% by weight after 24 hours of immersion in cold water.

What is the minimum thickness allowed for the outer shells and inner webs of the hollow brick?

The minimum thickness of any outer shell is 11 mm, and the minimum thickness of any inner web is 8 mm.

What are the common standard dimensions specified in this code?

Standard modular sizes are typically 190 x 190 x 90 mm, 190 x 90 x 90 mm, and 290 x 90 x 90 mm.

IS 3952

: 1988

burnt clay hollow bricks for walls and partitions - Specification

CurrentSpecializedSpecificationBIMMaterials Science · Clay and Stabilized Soil Products

Download PDF BIS Portal Google

This standard specifies the dimensions, physical requirements, and testing procedures for burnt clay hollow bricks used in load-bearing and non-load-bearing walls and partitions. It defines limits for compressive strength, water absorption, and efflorescence to ensure structural integrity and durability.

burnt clay hollow bricks for walls and partitions - Specification

Quick Reference Values

minimum compressive strength3.5 N/mm² (based on gross area)

maximum water absorption20% by weight

minimum shell thickness11 mm

minimum web thickness8 mm

permissible efflorescenceNot more than 'Slight'

Practical Notes

Hollow bricks provide excellent thermal and sound insulation and reduce the dead load of the structure compared to solid masonry.

Compressive strength must always be calculated based on the gross area of the brick, not the net area excluding voids.

Ensure bricks are thoroughly soaked in water before use to prevent them from absorbing moisture from the mortar, which weakens the bond.