Guideline for Labor for Brick Work in Super Structure

Brick work above foundation or floor level is known as brick work in super structure. There are two types of brick wall in super structure, one is load bearing and other is non load bearing. The load bearing wall in super structure transfers the load of RCC beam, slabs and live load coming on it to the foundation of the wall. Doors, windows and ventilators are fixed in the brick walls according to drawing and requirement.  Some time opening is left in the wall according to design without frame. The internal brick wall also helps to divide the building space into required component i.e. room etc. The outer brick walls serves the dual purpose as taking load and  used for ornamental/ architect design of the building.

Laying of brick work in Super Structure

There are number of brick laying arrangements called bonds. English bond is most commonly used in brick work for all wall thickness. Brick work shall be laid with the help of bricks soaked in water and cement mortar. Lay cement mortar layer 6mm to 9mm thick on the damp-proof course or plinth beam and on the bed of mortar, lays the bricks with frog of brick on up side. Care should be taken that all loose materials, dirt, set lumps of mortar which may be laying on the surface of damp-proof course or plinth beam on which brick work to be freshly started shall be removed with wire brush and surface to be wetted. While laying the brick sees the mortar bed is in full width and even. The bricks should be set in position by gently pressing and should be in straight line with the help of thread and also in plumb. After completing one coarse of bricks all joints should be filled with mortar. Joints shall be fully filled and packed with mortar such that no hollow space is left inside the joints.

Common defects in brick work and cement mortar

• Raw materials like brick, sand, cement and water are of sub standard quality without qualifying any test.
• Bricks are not soaked in water properly.
• The joints in brick works are thicker, unfilled properly.
• Raking of mortar is not done when the mortar is green.
• Bricks bats are used in masonry work.
• Mortar is not mixed properly on platform.
• There is improper mixing of cement mortar.
• There is excessive water content in mortar
• Brick work is not in plumb, level and straight line.
• Mortar is not according to the structural requirements.
• There is high suction of brick and less water retention of mortar
• There are uneven joints in brick works
• There are voids in vertical joints

Precautions in brick work

• The length and width of the walls in foundation should be according to the drawings. 
• The quality of bricks should be good having required strength and should not show any efflorescence (salt on face). 
• The sand should not have fine grains and be free from silt etc. The sand used for brick mortar should be of required FM (Coarser) with no silt.
• The mixing of mortar should be proper with required quantity of water. It should not be dry or liquid.
• The bricks are soaked in water before use otherwise these will absorb water from the mortar and the bonding will be weak
• The water should penetrate to the core of the brick but the brick should be skin dry i.e. from outside when it’s used in actual.
• The frog or depression side of the brick should be upwards.
• Minimum number of bats is used.
• Bricks are absolutely aligned horizontally and in a straight line. This can be checked by a stretched string across the face.
• The bricks are vertically aligned which can be checked with a plumb bob.
• The courses or layers of bricks are level. This can be checked with a spirit level.
• The thickness of joints is not more than 1 cm.
• The joints should be filled with mortar fully without any gaps.
• The joints are pushed inside when cement mortar is still wet so that later plastering can be done effectively.
• Brick work should be kept wet for seven days so that the mortar may gain its full strength.
• Bricks, sand and cement used in brick work should be according to their specifications
  

Tools recommended for brick work

• Wooden setting out square
• Spirit level
• Water level
• Boning rod
• Plumb rule
• Laying trowel
• Brick hammer
• Lump hammer and bolster chisel.
• Double end comb hammer
• Straight edge
• Brick work gauge rod