Thermal insulating masonry hollow bricks

A masonry hollow brick of a substantially rectangular cuboid shape with a top surface and a bottom surface, comprising:

• first and second outer central cavities having rectangular cross sections parallel to a rectangular cross section of the masonry hollow brick;
• an inner central cavity having a rectangular cross section that is disposed between and parallel with the first and second outer central cavities;
• and
• first and second rectangular side indentations having cross sections extending from a sidewall of the masonry hollow brick toward the inner central cavity;
• wherein:
• the top surface and the bottom surface are flat;
• the inner central cavity and the first or the second side indentations are not continuous;
• the first and second outer central cavities, the inner central cavity, and the first and second side indentations are continuous along a direction perpendicular to the cross section of the masonry hollow brick;
• and
• the length of each of the first and second rectangular side indentations is 12-18% relative to that of the rectangular cross section of the masonry hollow brick;
• the length of each of the rectangular cross sections of the first and second outer central cavities is 82-90% relative to that of the masonry hollow brick;
• the length of the rectangular cross section of the inner central cavity is 45-65% relative to that of the masonry hollow brick;
• the first and second outer central cavities and the inner central cavity are the only cavities present in the masonry hollow brick;
• and
• the masonry hollow brick is a cured form of a concrete composition comprising:
• cement;
• water;
• sand;
• an insulating material which is at least one selected from the group consisting of a perlite, a polyethylene, and a crumb rubber;
• and
• a coarse aggregate, which is not the insulating material.