This document provides specifications for plastering work and types of pointing in interior and exterior building works. It details requirements for materials like cement, sand, water and additives to be used for plastering. It describes the process of plastering including preparation of mortar, application methods and curing. It also explains different types of pointing in masonry - flush, ruled, cut/weather struck and raised cut pointing - and specifies the finishing and curing of pointed joints.

1. BUILDING
SPECIFICATION
DETAILED SPECIFICATION ON:
PLASTER IN INTERIOR, TYPES OF POINTING &
POINTING IN EXTERIOR
BY:
BRAHAMJYOT SINGH
GURJOT SINGH
MANHARPREET SINGH
AVNEET SINGH

2. DETAILED SPECIFICATION FOR
PLASTERING WORK IN INTERIOR
INDIAN STANDARDS :
Work shall be carried out to Indian Standards and Code of
practices. In absence, International Standards shall be followed.
These shall be latest issue.
List given here under is not to be considered as conclusive and is
for reference and guidance only.
Any discrepancies / conflict noticed shall be directed to the EIC
for his direction/approval. However, as a general rule more
stringent specification shall take precedence.

3. CEMENT :
MATERIALS :
 The cement shall be ordinary Portland Cement conforming to IS.
 Approved blended cement shall be used for internal plaster, masonry,
flooring, waterproofing and plumbing works.
 In case cement has been stored for over 6 months from date of
manufacturer or for any reasons the stored cement shows signs of
deterioration or contamination, it shall be tested as per the direction
of the Engineering- charge prior to use in the works.
WATER
 Water used for mixing and curing shall be clean, reasonably clear
and free from objectionable quantities of silt, oils, alkalis, acids,
salts so as not to weaken mortar.

4.  Water tested shall be in accordance with IS 3025. Maximum
permissible limits of deleterious materials in water as given in
IS 456-2000.
 Sand shall conform to IS 1542 specification for sand for plaster.
 Integral water proofing compound shall conform to IS 2645
(Specification for integral waterproofing compound)
 Neeru shall be obtained by mixing lime putty and sand in equal
proportions and chopped jute @ 4 kg/cum of mortar and ground
to fine paste in the chemical grinder to give fine butter-like
paste.
Approved ready-made neeru available may be permitted if
desired by the contractor after testing at site.

5. GI CHICKEN MESH / PLASTER MESH
 GI Chicken mesh of 20 gauge as approved shall be used over
junctions of concrete and masonry or two dissimilar materials about
150mm wide fixed with GI wire nails etc. as directed by the EIC.
BONDING AGENT
 Chemical bonding adhesive of approved chemical admixture
manufacturer’s shall be used as per recommendations of
manufacturer over concrete surface.
MORTAR
 Mortars shall be prepared by mixing fine graded aggregate with
cement, in the proportion specified for respective items of work
as detailed in the BOQ and drawings. Mixing of mortars shall be
done by mechanical PAN mixers or by hand mixing.

6.  Mortars shall be specified by proportion only and not by strength.
Volumetric mixing shall be based on dry volumes of each ingredient.
For convenience, measurement shall correspond to volume of one
cement bag i.e. 0.035 cu.m. Boxes shall be of size 40 x 35 x 25 cm.
CEMENT MORTAR :
 Cement mortar shall be prepared by mixing cement and sand in
specified proportions. Proportioning shall be carried out as detailed
above. Sand shall be added suitably to allow for bulkage if required.
Bulkage shall be determined as specified in IS 2386 Part-III.
 Cement and sand added to mixer shall be thoroughly mixed and water
shall be added to it gradually. After addition of water the mixer shall
run for a minimum of 3 minutes. The mortar mixed shall be consumed
within 30 minutes of its mixing.

7. WORKMANSHIP
 Mixing shall be done mechanically using PAN mixer only. Each
mortar batch shall be used within half an hour. The mixing operation
shall be continued with addition of necessary quantity of water until
a uniform appearance and consistency of mortar is obtained.
 Cement and sand shall be mixed dry in required proportion to obtain
a uniform color and water shall then be added to get the required
consistency for the plaster.
METHOD OF PLASTERING
 Surfaces to be plastered must be clean and free from dust, loose
material, oil, grease, mortar droppings, sticking of foreign matter,
traces of algae, etc.
 Walls should be sufficiently damp prior to plastering. Water from
plastering mortar must not be absorbed by masonry under any
condition.

8.  Any unavoidable projections in masonry and concrete surfaces
shall be chiseled back. Care shall be taken that surrounding
surfaces are not damaged and reinforcement is not exposed.
 Thickness of one coat should not be more than 15mm and less
than 8mm for single coat finished plaster.
 The method of application is also important and hence it is
recommended that the mix be thrown on the surface rather
than stuck with trowel. This increases the adhesion.
 Plaster shall be cured for 14 days by wet curing except in wall
care putty finish plaster. During this period plaster shall be
protected from exposure to extremes of temperature and weather.
 Plaster shall be leveled and lined by aluminum hollow section, 2-3
m long. (This will give even and leveled surface). There shall not
be more than 2mm difference in level when checked with 3m
straight edge. It is important that enough pressing and beating is
done to achieve compact filling of joints and that the area is fully
compacted.

9.  Finishing of plaster may be carried out with wooden float
(randhas) or trowelled smooth with sheet metal trowels as
specified. Care shall be taken to avoid excessive trowelling and
overworking of the wooden float.
 It is advisable to limit the area of plaster to 15 sq.mt. to avoid
cracks due to thermal movements of dissimilar material in contact,
it is advisable to provide joints treated with groove or any other
detail as suggested by the Architect. These joints if not specified
shall be treated with 150mm wide reinforcing chicken mesh
(approved by the EIC) fixed over joints by GI nails and the area
plastered.
 Plaster shall be cut to correct horizontal or vertical line at the end
of the day or if work requires to be suspended for any reason.
 All corners, internal or external, shall be truly vertical or
horizontal. These shall be finished with a proper template to
achieve best workmanship for rounding and chamfering as
specified or directed.

10. PREPARATION FOR
POINTING AND GROUTING
Preparation of surface
 The joints shall be raked out properly. Dust and loose mortar shall be brushed
out. Efflorescence if any shall be removed by brushing and scraping. The
surface shall then be thoroughly washed with water, cleaned and kept wet
before pointing is commenced.
 In case of concrete surface if a chemical retarder has been applied to the form
work, the surface shall be roughened by wire brushing and all the resulting
dust and loose particles cleaned off and care shall be taken that none of the
retarders is left on the surface.
 The joints shall be raked to such a depth that the minimum depth of the new
mortar measured from either the sunk surface of the finished pointing or from
the edge of the brick shall not be less than 12 mm.

11. Mortar
 Mortar of specified mix shall be used.
 13.13.4 Application and Finishing
 13.13.4.1 The mortar shall be pressed into the raked out joints, with a pointing
trowel, either flush, sunk or raised, according to the type of pointing required.
The mortar shall not spread over the corner, edgesor surface of the masonry. The
pointing shall then be finished with the proper tool, in the manner described
below:
 13.13.4.2 Flush Pointing : The mortar shall be pressed into the joints and shall be
finished off flush and level with the edges of the bricks, tiles or stones so as to give
a smooth appearance. The edges shall be neatly trimmed with a trowel and straight
edge.
 13.13.4.3 Ruled Pointing : The joints shall be initially formed as for flush pointing
and then while the mortar is still green, a groove of shape and size as shown in
drawings or as instructed, shall be formed by running a forming tool, straight along
the Centre line of the joints. This operation shall be continued till a smooth and hard
surface is obtained. The vertical joints shall also be finished in a similar way. The
vertical lines shall make true right angles at their junctions with the horizontal lines
and shall not project beyond the same.

12.  13.13.4.4 Cut or Weather Struck Pointing : The mortar shall first be
pressed into the joints. The top of the horizontal joints shall then be neatly
pressed back about 3 mm or as directed, with the pointing tool so that the
joints are sloping from top to bottom. The vertical joints shall be ruled
pointed. The junctions of vertical joints with the horizontal joints shall be
at true right angles.
FINISHING
 13.13.4.5 Raised and Cut Pointing : Raised and cut pointing shall project
from the wall facing with its edges cut parallel so as to have a uniformly
raised band about 6 mm raised and width 10 mm more as directed.
 13.13.4.6 The superfluous mortar shall then be cut off from the edges of the
lines and the surface of the masonry shall also be cleaned off all mortar. The
finish shall be such that the pointing is to the exact size and shape required
and the edges are straight, neat and clean.
 13.13.5 Curing : The pointing shall be kept wet for seven days. During this
period it shall be suitably protected from all damages. The pointing lines
shall be truly horizontal and vertical except where the joints are slanting as
in Rubble random masonry. Lines of joints from different directions should
meet neatly at the junctions instead of crossing beyond.

13. THANK
YOU…