Plastering provides a finished surface that is firm and smooth.
The plaster acts as a sound and thermal insulation layer to some extent.
Plaster is a layer of cement-sand mortar applied over a masonry work which also acts as a damp-proof coat over the masonry.
Plastering enhances the appearing of the building.
Helps to provide a suitable base for colour wash.
The first coat of cement plaster is carried out in cement mortar of proportion 1:4,I.e. one part of cement to four parts of clean,coarse and angular river sand by volume.
The thickness of first coat is 12mm.
The first coat is to be well watered for atleast 7 days.
The first coat is provided with zigzag lines so that the first coat adheres well with the second coat.
The second coat of sand-faced cement plaster is carried out in proportion 1:3 and the thickness of second coat is 8mm.
The second coat should be applied on the first coat before 7 days of completion of first coat.
Sand to be used in the mortar for the second coat is to be perfectly screened so that sand of uniform size appears on the surface.
Sponge is used on the second coat and it is applied when the second coat is wet and it is so worked that the density of sand grains appearing on the surface is equal and uniform.
After completion of the second coat, the surface is kept well-watered at least for 15 days.
DEFECTS IN PLASTERING
Blistering or plastered surface
FOR MINIMISING DEFECTS IN PLASTERING WORK
The brick and plastering work should be carried out by skilled masons in the best workmanship manner.
Bond of brick should be properly maintained.
The surface to be plastered should be well-watered so that it may not absorb water from plaster.
Excessive trowelling should be avoided.
Fresh plaster surfaces should be protected from rain,dirt and excessive heat as sun.
Water free from salts should be used for brick work and plastering work.