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Brick masonry is a unit of construction made by bonding brick units together by mean of either cement or lime mortar and sometimes with mud mortar. Brick masonry is not as strong as stone masonry but when compared in cost aspect it is economical. Brickwork forms a major part of building construction, it costs about one-fifth to one- fourth of the cost of the building. Brick procured at the site of work shall be soaked in water before use. The soaking shall be such that water penetrates the whole mass of the brick. The period of soaking will depend upon the time taken for such penetration. One hour time for soaking is considered the minimum period. Longer period of soaking helps dissolution of salts present in the brick.
Soaking of bricks results in the following advantages:
- It assists in removing the dirt, earth, ash and dust from the bricks.
- It prevents the suction of water from the wet mortar as otherwise the mortar is likely to dry out soon and crumble without attaining any strength.
- It helps leaching out soluble salts from the bricks and if water is frequently changed it reduces afflorescence
- It reduces breakage of bricks while making special brick bats and queen closures which are required for proper bonding and breaking joints.
Soaked bricks will be removed from the water sufficiently ahead of the time of laying and allowed to become skin-dry. They shall be stacked on a clean place just before use where they are not again spoiled by dirt, earth etc. The bricks shall not be too wet at the time of use since too much water on the surface will cause the brick to slide out of line on the bed of mortar and the wall is likely to go out of plumb.
Bricks in the facing are laid in alternate courses of headers and stretchers. The header course is commenced with a header brick followed by a queen-closure and is continued with successive headers. The stretcher course is commenced with a stretcher. It should have a minimum lap of one-quarter of its length over the header. The laying of headers and stretchers goes on alternatively. The final course (i) at the top the plinth (ii) at just below the roof slab (or floor slab) and (iii) at top of the parapet shall be laid with bricks on edge.
Bricks shall be laid on a full bed of mortar. When laying, the bricks shall be slightly pressed so that the mortar can get into all the pores of the brick surface to ensure proper adhesion. Cross joints and bed joints shall be properly flushed and packed with mortar so that no hollow spaces are left. Properly filled joints ensure maximum strength and resistance to penetration of moisture which takes place mainly through joints.
The mortar should contain as much water as possible to fill in the joints properly. Water should not be poured on the bed and in the joints after the mortar is laid or filled. The mortar should be in plastic state when bricks are laid and in such quantity that an excess will squeeze out on all sides of the joint when brick is shoved into place.
During construction period all works should be protected from weather. The faces of brickwork shall be cleaned with wire brush so as to remove any splashes of mortar during the course of raising the brickwork.
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