Masonry

Masonry is construction from individual units, bricks, concrete blocks, stone or autoclaved aerated concrete blocks, bound together with mortar. It is strong in compression, weak in tension, durable, fire-resistant and good at storing heat and blocking sound, which is why it remains the most common walling in Indian buildings.

Bricks are laid in bonds so that vertical joints in one course do not line up with those in the next; English bond, alternating courses of headers and stretchers, and Flemish bond, alternating headers and stretchers in each course, are the classic patterns for walls one brick thick and more. Good practice includes soaking clay bricks before laying so they do not suck water from the mortar, filling all joints, keeping courses level and walls plumb, limiting the height built in a day, and curing the work.

Mortar is usually cement and sand, sometimes with lime for workability and better bond. Richer mixes such as 1 : 4 suit load-bearing piers and exposed work; leaner mixes such as 1 : 6 suit ordinary walls. Mortar should not be much stronger than the units, so that any cracking occurs in the joints and can be repaired.

Load-bearing masonry is designed for compression with allowance for slenderness and eccentricity, using permissible stresses that depend on unit strength and mortar grade. In seismic areas, horizontal bands at plinth, lintel and roof level, vertical bars at corners and limits on openings are needed. Brickwork practice in India is covered by IS 2212 and structural design by IS 1905.