Hollow concrete blocks are primarily used as building materials in the construction of walls, and commonly used in compound walls due to their low cost. They are also more useful due to their lightweight and ease of ventilation. These concrete blocks are made of a mixture of cement, sand and stone chips. Construction with hollow blocks provides facilities for concealing electrical conduits, water and sewerage pipes. It also saves cement in masonry work, bringing down the cost of construction considerably.
The first hollow block was designed in 1890 by Harmon S Palmer in the United States. After 10 years of experimenting with his notion, he patented the design in 1900. By 1905, an estimated 1,500 companies were manufacturing concrete blocks in the United States. These early blocks were usually cast by hand, and the average output was about 10 blocks per person per hour.
Today, concrete block manufacturing is a highly automated process, producing up to 2,000 blocks per hour. Initially, concrete blocks were used in the United States as a substitute for stone or wood in the building of homes. Gradually with time, the homes built of concrete blocks showed a creative use of common inexpensive materials made to look like the more expensive and traditional wood-framed stone masonry building. This new type of construction became a popular form of house building in the early 1900s through the 1920.
Fast forward to modern times, construction with hollow concrete blocks and bricks are very popular throughout the world, and in Bangladesh, with the recent implementation of the government commitment from 2019 to reduce climate and environmental hazards, hollow concrete blocks and bricks are paving their way in government projects as well as non-government ones, replacing the local red clay bricks.
The benefits of using hollow concrete blocks
Economic substructure design due to reduction of loads
Saving in mortar for laying of blocks as compared to regular red clay bricks.
Insulation of walls is achieved due to cavities, which provides energy saving for all times. Similarly hollowness results in sound insulation.
Paint on finished walls can be applied due to cavities, which provides energy saving for all times. Similarly hollowness results in sound insulation.
No problem with the appearance of salts. Hence, great saving in the maintenance of final finishes to the walls.
Laying of blocks is much quicker as compared to regular brickwork, therefore saves time.
Thermal insulation property of hollow concrete blocks is more than ordinary brick walls.
Hollow concrete blocks are environmentally ecofriendly.
The safety factor of hollow concrete blocks is more than brick masonry.
Maintenance cost of the hollow concrete block is less than brick masonry.
Hollow concrete blocks may be a relatively new phenomenon in construction in Bangladesh, but given the obvious advantages, it will rapidly emerge as one of the first choices in quality construction projects. Bangladesh is developing at a rapid pace, and these hollow concrete blocks are a durable value addition to the development.