Preparation of surface
The joints in brickwork shall
be raked out to a depth of 19 mm (3/4”) minimum. The surface shall be brushed
to remove any dirt accumulated. The brickwork shall be thoroughly wetted on the
previous day to ensure that the surface does not absorb water from cement
mortar.
Preparation of cement mortar
(1:5)
Cement and sand of standard
quality satisfying I.S. requirements are mixed dry in the proportion of 1 part
by volume of cement to 5 parts by volume of sand until a uniform colour is
obtained. Water is then added with a rose and the mortar is mixed again so as
to obtain a uniform workable mix. Mixing operation is done on a impermeable
platform.
The mortar will be dashed
against the surface and well pressed to the required thickness of 13 mm. to
obtain uniformity in thickness patches of 15 cm x 15 cm are firstly prepared at
top, bottom of wall at intervals of 6 m and checked for plumb. The remaining
wall between these patches is then plastered and finished by means of a wooden
float and trowel. The edges of windows, columns etc, are either straightened or
rounded off as required.
The plumb line and level is
constantly checked to present a true, uniform surface.
The surface is then finished
with neeru to obtain a smooth texture.
The plaster is wetted continuously
for at-least 14 days to (cured) achieve good strength. Curing is started on the
next day of application of plaster so as to allow the mortar to set completely.
Unit of measurement
The mode of measurement for plaster is ‘m2’.
The work should be done in such
a way so that the Engineer in-charge approves the quality of the work.
