Lightweight bricks can be produced by mixing the expanded perlite, CMC, coal dust and water. However, it may not achieve some of the physicomechanical properties. Therefore, colemanite is chosen in the present study to obtain lightweight bricks with high strength, heat and sound insulating and neutron shielding properties in the field of construction. The bricks were prepared by using different amount of colemanite (0-20% by weight) at different temperatures (200-400 degrees C). Optimum physicomechanical property of the brick was obtained after the heat treatment at 400 degrees C when 10% colemanite was added into the brick. Its physicomechanical properties (compressive strength, point loading index, unit weight, ultrasonic transit speed, water adsorption, porosity, heat and sound conductivity and sound insulation and neutron shielding effectiveness) were compared with the commercial lightweight construction bricks (normal brick, sandwich brick, gas concrete and pumice block). Our results indicated that brick studied in this article had better physical properties than the other construction bricks. (C) 2014 Elsevier Ltd. All rights reserved.