finishing works in building including cladding,plastering, pointing works , suspended ceiling , partition walls, paints and painting procedures as per ioe syllabus ,

1. CONTENTS
 9.1 Cladding(Types, Fixing Process)
 9.2 Partitions And Suspended Ceiling
 9.3 Plastering And Pointing(Types And Process of
Application)
 9.4 Painting Works in wooden, Metal and Masonry Surfaces
1

2. CLADDING
In building construction, the material applied on the
surface of wall is Cladding.
Generally it is non load bearing; it does not take up or
transfer load of the structure.
Made up of brick,
stone,wood,concrete,plastic,metal,etc.
Note: When main structural materials like stone or brick
are laid and dressed to provide external surface ,they act
as load bearing.
2

3. FUNCTIONS
 Provide necessary resistance to rain penetration.
 Resist both positive and negative wind pressures.
 Provide necessary resistance to wind penetration.
 Give required degree of thermal and sound insulation.
 Give required degree of fire resistance.
 Provide sufficient openings for admittance of natural
light and ventilation.
 Increase the durability of the wall by providing weather
resisting coat.
 Aesthetic purpose
3

4. Types of Cladding
1.Brick Cladding
2.Stone Cladding
3.Concrete Cladding
4

5. Brick Cladding
Brick panels are non-load bearing claddings.
Can be used in stone,brick as well as concrete
backing.
Traditional bricks of trapezoidal shape can be used as
cladding.
Machine cut bricks(Chinese) works as load bearing
cladding.
Framed structured buildings mostly have brick
cladding.
Brick tiles are available in different shape, size and
color, which are used for brick facing.
Held in place with plasters and mortars or sometimes
clamps. 5

6. 6

7. Fixing Process
 The panels are supported at each structural floor and
tied at vertical edges.
 Butterfly wall ties are cast in to the column and built
in to the brick joints at every fourth course.
 Galvanized pressed steel dovetail slots are cast into
the column and dovetail anchors are used to form the
tie.
7

8. Pros And Cons of brick Cladding
 Resistant and safe
 Easy to maintain
 Fireproof material
 High cost and precision of
installation
This Photo by Unknown Author is licensed under CC BY
8

9. Stone Cladding
 Stone are popular cladding material.
 These are thin layers of stone, slate
stones or any sedimentary rocks.
 Applied on normal brick backing or
random rumble stone backing.
 Can also be laid on the concrete backing.
 Normally, small in size
 Have cement mortar bedding on the wall
9

10. 10

11. Concrete Panel cladding/Concrete cladding
 Common in large construction mass housing,
industries, high-rise buildings, and retaining
structures.
 Usually pre-fabricated concrete panels with
textured face fixed over the original surface
to provide desired surface.
 Mostly used in high risk reasons from
weather.
This Photo by Unknown Author is licensed under CC BY-SA
11

12. Precast CC 12

13. Requirements
 Concrete panels are constructed of dense
concrete with suitable steel reinforcements.
 When designing a concrete panel following
points are taken into account;
• Column or beam spacing,
• Lifting capacity of the plant,
• Joining methods,
• Exposure conditions,
 Any special planning requirements as to finish
or texture.
 There can also be cladding of concrete on
brick or stone backing 13

14. 14

15. 2.Partitions and suspended ceilings
2.1 Introduction to partitions
2.2 Advantages
2.3 Requirements of good partitions
2.4 Types of partitions
2.5 Suspended ceilings, uses
2.6 Requirement of good suspended ceiling
2.7 Types
Partition wall
False ceiling
15

16. Partition walls
Glass partition
16

17. Partition walls
 Vertical walls or panels used to divide room or portions of
buildings
 A partition wall may be defined as a wall or separation made
up of bricks, timber, glass or other such material and provided
for the purpose of dividing one room or portion of a room
from another.
 The partition walls are constructed either over the beam or
floors. In case, constructed over floor they need to be
supported with concealed beams.
17

18. Advantages of partition walls
 Divide the whole area into many rooms.
 Provide privacy to the inmates from sight and sound.
 Partition walls are light in weight and cheaper in cost of construction
 Occupy less floor area (due to thin section)
 Easy to construct in any position
18

19. Requirements of a good partition wall
 Should be thin in section to utilize maximum floor area.
 Should provide adequate privacy in rooms in both sight and sound.
 Should use durable and light material.
 Should be simple, easy and economic in construction.
 Should resist both heat and dampness.
 Should be rigid enough to take the vibration caused due to loads.
 Should be strong enough to support sanitary fittings and heavy fixtures.
 Should be strong enough to carry its own load.
 Should resist fire.
19

20. Types of partitions
1.On the basis of load transfer mechanism.
a)Load bearing partition
b)Non-load bearing partition
2. On the basis of materials used.
a)Brick partitions
b)Hollow block partitions
c)Concrete partitions
d)Glass partitions
e)Timber partitions
f)Metal partitions
g)Ac sheets partitions
20

21. a) Load bearing partitions
 Designed and constructed to
receive the superimposed
load and transfer it to the
foundation.
 Generally, constructed with
bricks, hollow/solid blocks.
 Lintels are used to span
openings.
 Load bearing walls support
the joints of the floor, purlins
and ceilings just off the roof.
21

22. b) Non load bearing walls
 Neither receive
superimposed load nor
transmit any structural
loads to the sub-structure.
 It has only its self weight to
hold in position.
 It can resist impact loading
on its face and vibrations
caused due to any reason.
 It also carries fixtures and
fitting required in the room.
22

23. a) Brick partitions
 Brick partition walls are constructed with plain bricks , reinforced
bricks, and brick noggings
 Plain brick partition of half brick thickness should not be more than
2m in height.
 Reinforced brick partition is similar to plain brick partition but is
much stronger due to the placement of reinforcements.
 Reinforcements, which is in from of wire mesh strips or iron bare,
are placed at every third or fourth course.
 Brick nogging partition wall consists of brickwork built within a
framework of wooden members.
 Fireproof and soundproof
 Widely used in context of Nepal
23

24. Brick partitions
Brick Noggings
24

25. b) Hollow block partitions
 Hollow blocks of concrete or
clay(terracotta) are used.
 They are light in weight, rigid and
economical in construction.
 For the ease of construction , the
hollow blocks are provided with
grooves on top, bottom and the sides
of the blocks. The grooves provides
rigid joints and serves as a key to
plaster.
 The cavities in hollow block shouldn’t
exceed 25% of total mass.
 Provides thermal resistant
25

26. c) Concrete partitions
 It consists of concrete slab, plain
or reinforced, supported
laterally by vertical members.
 These slabs may be either
precast of cast in situ.
 Special concrete posts are used
for pre cast concrete partition
walls
26

27. d) Glass partitions
 Are made up of sheet glass
or hollow glass blocks.
 Sheets of glass are fitted in
metallic or wooden
framework
 Are damp, sound, fire and
heat proof.
 Easy to clean and maintain.
 Provides good aesthetics and
allows light.
27

28. e) Timber partitions
 Lighter in weight and easy to
construct.
 Not suitable for damp places.
 Neither sound nor fire proof.
28

29. f) Metal partitions
 Are light in weight, fire proof
and strong.
 Are easy to construct and
shift.
 Insulated materials are filled
inside hollow spaces.
 Used in office and industrial
buildings .
29

30. suspended ceilings
30

31. Suspended ceilings
 Suspended ceilings are secondary
ceilings suspended from the
structural floor slab above,
creating a void between the
underside of the floor slab and
the top of the suspended ceiling.
 Its also called as false ceiling.
 Metal grids are hung with the help
of suspenders which are
connected to hooks in structural
floor.
 And compatible panels are then
placed on the grid framework
beneath.
31

32. Uses of suspended ceilings
 To provide aesthetic appearance.
 The void created is used to accommodate the electrical wires,
plumbing pipes ,light fittings, air conditioning services, etc.
 Enhances thermal and sound insulation.
 Safety purpose.
32

33. Requirements of a good suspended ceilings
 Easy to construct.
 Easy to clean , repair and maintain.
 Must follow building standard and norms of building of the
region.
 Should provide any required acoustic control in terms of
absorption and reverberation.
 Light in weight.
33

34. Types of suspended ceilings
a)On the basis of materials:
1)timber
2)RCC
3)metal
4)gypsum board
5)glass
34

35. Types of suspended ceilings
b) On the basis of method of construction.
1)Joint-less ceiling
2)Panelled ceiling
3)Open ceiling
35

36. Types of suspended ceilings
1)Joint-less ceiling:
 These forms of suspended ceilings provide a continuous and
jointless surface with the internal appearance of a
conventional ceiling
36

37. Types of suspended ceilings
2)Panelled suspended ceilings:
 most popular form of
suspended ceiling.
 consists of a suspended grid
framework to which the ceiling
covering(tile, tray, board) is
attached.
37

38. Types of suspended ceilings
3) Open ceiling:
 Frame is fixed in such a way
that voids are forms to give
illuminated effects.
 Mainly constructed for
decorative purpose.
38

39. 40
Plastering
• Applying mortar coats on
the surfaces of walls,
columns, ceiling etc. to get
smooth finish.
• lime or cement mortar.
https://wallpaperaccess.com/full/4339714.jpg
39

40. 41
Purpose of Plastering:
https://stock.adobe.com/search/images?k=before+after+con
struction&asset_id=180501428
• Good Appearance
40

41. 42
Purpose of Plastering:
https://stock.adobe.com/search/images?k=before+after+con
struction&asset_id=180501428
• Good Appearance
• Smooth Surface
41

42. 43
Purpose of Plastering:
http://actionwallties.co.uk/awt/wp-content/uploads/2019/02/case-
study-56e19a8525f9e9.55425313.jpg
• Good Appearance
• Smooth Surface
• Conceals Defects
42

43. 44
Purpose of Plastering:
https://civildigital.com/wp-
content/uploads/2018/01/Corrosion-of-RC-structure.jpg
• Good Appearance
• Smooth Surface
• Conceals Defects
• Protects from exposure
43

44. 45
Requirement of Good Plaster:
https://i6v8f2y6.stackpathcdn.com/wp-
content/uploads/2017/03/cement-sand-water-for-Plastering.jpg
• Adhere easily
• should be hard and durable
• prevent moisture
penetration
• should be cost effective
44

45. 46
Types of Plaster:
https://thumbs.dreamstime.com/b/collapsed-lime-plaster-
wall-old-house-background-texture-215772220.jpg
• Lime Plaster
45

46. 47
Types of Plaster:
https://image.slidesharecdn.com/5-150727163527-lva1-
app6891/95/5plastering-1-638.jpg?cb=1438015087
• Lime Plaster
• Cement Plaster
46

47. 48
Types of Plaster:
http://www.johntyman.com/nepal/n323.jpg
• Lime Plaster
• Cement Plaster
• Mud Plaster
• Surkhi Plaster
• Bajra Plaster
47

48. 49
Method Of Plastering:
1. Preparation of Surface
Background and Ground
Work
https://i0.wp.com/civiconcepts.com/wp-content/uploads/2020/08/Cleaning-Dust-
from-Plastering-wall.jpg?resize=615%2C574
48

49. i) Keep mortar joints rough
ii) Clean joints and surface
with wire brush
iii) Deal with smoothness,
projection and cavities
(12 mm)
iv) Wash the wall
50
Method Of Plastering: 49

50. 12
Method Of Plastering:
https://i0.wp.com/civiconcepts.com/wp-content/uploads/2020/08/Cleaning-Dust-
from-Plastering-wall.jpg?resize=615%2C574
i) For uniform thickness, fix dots
(150 mm x 150 mm, 10 mm
thick)
ii) Fix dots horizontally and then
vertically at distance of 2 meters
to cover entire wall
iii) Check verticality by plumb bob
iv) Screeds- vertical strips of plaster
50

51. 13
Method Of Plastering:
1. Preparation of Surface
Background and Ground
Work
2. Application of Rendering
Coat
https://i.ytimg.com/vi/2N1PEBs24Kk/max
resdefault.jpg
51

52. 14
Method Of Plastering:
https://i.ytimg.com/vi/2N1PEBs24Kk/max
resdefault.jpg
i) Brick masonry- 12 mm
thickness, stone masonry- 9 to
15 mm thickness
ii) C : S varies between 1:3 to 1:4
iii) Apply first coat by means of
trowel, level with floating rule
iv) Leave it to set but not to dry,
roughen it to apply second coat
52

53. 15
Method Of Plastering:
1. Preparation of Surface
Background and Ground
Work
2. Application of Rendering
Coat
3. Application of Final Coat
https://integrationbuilders.com/wp-
content/uploads/2020/05/plastering.jpg
53

54. 16
Method Of Plastering:
https://integrationbuilders.com/wp-
content/uploads/2020/05/plastering.jpg
i) Thickness between 2 to 3 mm.
ii) C : S ratio varies between 1:4
to 1:6
iii) From top towards bottom,
complete in one operation to
eliminate joining marks
iv) Keep it wet by sprinkling water
upto 7 days to develop
strength and hardness
54

55. 17
Tools Used for Plastering:
Trowel Float
Floating Rule
55

56. 18
Pointing
• special mortar finishing
work is done to the
exposed joints only.
• gives perfection to weaker
part of masonry
• adds aesthetic view
https://www.thespruce.com/thmb/G3vZOCqM81R1ycNgweKq1ywUdxw=/2124x1411/filters:fill(
auto,1)/Repointingbrick-GettyImages-182176654-e73eae4f63f6482995dda355f8b6985d.jpg
56

57. 19
Purpose of Pointing
• Protection from adverse
effect of atmosphere
• give better appearance
• Prevention of entry of
water
• economy to plaster
https://i.ytimg.com/vi/qD3hnrU_t18/max
resdefault.jpg
57

58. 20
Procedure of Pointing
• Joints are raked to about 10 mm depth.
• Raked joints are cleaned by using brushes.
• Joints are kept wet for few hours.
• Mortar is applied on the joints by means of small trowel.
• Applied mortar is given the shape of desired type of pointing
by using pointing tool.
• Curing is done for 3-10 days.
https://i.ytimg.com/vi/qD3hnrU_t18/max
resdefault.jpg
58

59. 21
Types of Pointing
https://tutorialstipscivil.com/wp-content/uploads/2020/11/Different-
Types-of-Pointing-03-0205110011.jpg
59

60. Painting Works 60

61. Painting Work Outline
Objectives of painting work
Types of paint
Painting on different surfaces
Defects in painting
61

62. Objectives
 Protection
 Prevention from wood decay and corrosion in metal
 Aesthetics
 Smooth surface
 Hygienically safe and clean surface
62

63. Source: www.alamy.com
63

64. Source: https://blogs.worldbank.org
Source: @officialroutineofnepalbanda
Smooth Surface
Rough Surface
64

65. Characteristics of Ideal paint
 Spreadability
 Economical
 Easy to apply on surfaces
 Color durability
 Hard and durable surface after application on surface
 Hygienic (During and after the application)
 Should not form cracks on drying
 Adequate fire and moisture resistant
 It should form thin film of uniform nature
 It should possess attractive and pleasing appearance.
65

66. What is Paint?
66

67. Components of Paint
Paint is very complex material consisting of many components. Modern paints can
have 10 to 20 components, each responsible to give specific quality to the paint.
Major components of a typical oil based paint are:
 Base
 Vehicle
 Pigments
 Drier
 Thinner
67

68. Base
 Major component
 Holds binding property
 Forms opaque coating
 e.g. Lead paints, Zinc paint, lithophone etc.
Vehicle
It is an oily liquid in which the base and pigment are soluble.
It facilitates the paint to be conveniently spread evenly over the surface by means o
a brush.
It acts as a binder for the base and cause it to stick to the surface.
On drying it forms a tough and an clastic film.
Oils most commonly used as vehicles are : Linseed oil, Poppy oil. Nut oil and Tung
oil.
68

69. Pigments
 These are finely ground colouring matters.
 Their main function is to give colour and opacity to the paint.
 Pigments are liable to fade because of the bleaching action of sun rays
Black- Lamp black, vegetable black
Blue- Indigo, Prussian blue, Copper Sulphate.
Green-Iron sulphate (Copper displace by iron)
Red-Red lead, vermillion
Solvent or Thinner
 A liquid thinner is added to the prepared paints to increase their fluidity to the
desired consistency so as to make them work more smoothly and also to help
penetration of porous surfaces.
 Most commonly used solvent is oil of turpentine.
69

70. Drier
 Driers are added to paints to quicken the drying of vehicles
Absorb O₂ from air and supply to vehicle for hardening
 Some of the commonly used driers are : Litharge, Red lead, lead acetate,
Manganese dioxide and Zinc sulphate
70

71. Types of paint
 Aluminum Paint
 Anticorrosive Paint
 Asbestos Paint
 Bituminous Paint
 Cellulose Paint
 Cement Paint
 Colloidal Paint
 Emulsion Paint
71

72.  Enamel Paint
 Graphite Paint
 Inodorous Paint
 Luminous Paint
 Oil Paint
 Plastic Paint
 Silicate Paint
 Synthetic Rubber Paint
72

73. Aluminum Paint
Finely ground Aluminum is suspended in either quick drying spirit varnish or slow
drying oil varnish.
 It gives an extremely metallic finish and glossy touch.
 It resists heat to a certain degree. (150 degree C)
 Iron and Steel surfaces are best protected.
 Possesses a high covering capacity.
 i.e. 1 liter of paint can cover an area of 200 m²
Gives good appearance.
Good moisture resistant.
High electrical resistance.
Widely used for painting gas tanks, hot water pipes, marine piers, oil storage
tanks etc.
73

74. Anticorrosive paint
It essentially consist of oil and strong drier. It consist pigments such as chromium
oxide, lead, red lead or zinc chromate.
It is cheap.
Durable.
The appearance of the paint is black.
Asbestos paint
It is a peculiar type of paint and applied on the surfaces which are exposed to
acidic gases and steam.
74

75. Bituminous Paint
This paint is prepared by dissolving asphalt or mineral pitches or vegetable
bitumen in any type of oil or petroleum.
Many varieties of Bituminous paint are available.
This paint presents black appearance.
It is mostly used for painting ironwork under water.
Cellulose Paint
This paint is prepared from nitro-cotton or celluloid sheets.
This paint hardens by evaporation of thinning agent.
It hardens quickly.
Surface painted with Cellulose paint can be washed and easily cleaned.
It is not affected by hot water and the surface can withstand extreme degree of
cold and heat.
75

76. Cement Paint
This paint consists of white cement,
pigment, accelerator and other additives.
It is available in dry powder form.
It is supposed to provide on rough surfaces
rather than on smooth surfaces because of
its adhesion power.
Note: For tropical countries like Brazil, Mexico,
Malesia; utmost care should be taken while
applying cement paint.
76

77. Advantages of Cement Paint
It requires less skill and time for applying this paint on surfaces.
The applying implements can be cleaned with water only.
Preparation of surfaces is easier for cement paint system as it is not necessary to
remove the previous coats of cement paint
It is suitable for painting fresh plasters having high alkalinity because cement
paints are not likely to be attacked by the alkalinity of masonry surfaces.
They become an integral part of the substrata and add to its strength.
They can be applied over new and damp walls which cannot be painted over
with oil paints until they are sufficiently dried.
They prove to be economical as compared to the oil paints and they dry more
rapidly than the oil paints.
77

78. Colloidal Paint
No inert material is mixed in this type of paint.
It requires more time to settle and in the process of settlement it penetrates
through the surface.
It may be used for interior as well as exterior walls.
78

79. Emulsion Paint
It contains binding materials such as polyvinyl acetate, synthetic resins etc.
This paint is easy to apply and dries quickly in about 1.5 to 2 hours.
It is durable.
It can be cleaned by washing with water. (water based paint)
It is odorless and possesses excellent alkali resistance.
For better service life, it is recommended to apply two coats of emulsion paint
For rough cement plastered surface, a thin coat of cement paint may first be
applied to smoothen the surface.
79

80. Enamel Paint
This paint is available in different colors.
It is a oil based paint.
It contains white lead, zinc white, oil, petroleum spirit and resinous matter.
It is resistant to acids, alkalies, fumes of gases, hot and cold water, stream etc.
It can be used for both internal as well as external walls.
For better appearance, it is desirable to apply a coat of titanium white in pale
linseed oil before the coat of enamel paint.
80

81. Graphite Paints
 This paint presents a black color.
 It is mostly used to apply on iron surfaces which come in contact with
ammonia, chlorine, Sulphur gases, etc.
 It is also used in mines and underground railways.
 Conductive paint.
81

82. Luminous Paint
This paint contains calcium sulphide with varnish. The surface on which this paint is
applied shines like radium dials of watches after the source of light has been cut off.
The paint should be applied on the surfaces which are free from corrosion.
Used for Fire exit, runway and so on. (Fluorescence)
Oil Paint
This is the ordinary paint and it is applied in three coats of varying composition.
They are respectively termed as primes, undercoats and finishing coats.
This paint is cheap and easy to apply and possesses good opacity and low gloss.
82

83. Plastic Paint
 The paint contains necessary variety of plastics and available in market in
different trade names.
 Its application can be done by brush painting or spray painting.
 This paint possess pleasing appearance.
 This paint is widely used for showroom and auditoriums.
83

84. Silicate Paint
This paint is prepared by freshly prepared by mixing calcined and freshly ground
silica with resinous substances.
The paint when dried forms hard surface and it is durable.
It can stand extreme heat and and it adheres firmly to brick work also.
It is not affected by alkalis.
No chemical action takes place on metal by this paint.
The silicate paint can directly be applied on the brick, plaster or concrete surfaces.
These surfaces should be made wet before the paint is applied.
Note: The surface should not be painted with silicate paint in hot weather.
84

85. Synthetic rubber paint
This paint is prepared from resins. It has following advantages.
It offers good resistance to water and is not affected by heavy rains.
It dries quickly.
Excellent abrasion resistance.
The uniform color is maintained when the paint is applied on the surface.
It can be applied not only on concrete surfaces but also on (asphalt) roads.
It can be applied on surfaces which are not completely dry e.g. fresh concrete.
It is moderate in cost and covers sizeable area.
It possesses excellent chemical resisting property.
85

86. Some points related to painting
Brushes
New brushes should be soaked in water up to level of bristles for period of 2 hours
and then they should be allowed to dry for a period of about 1 hour.
During painting, the brush should be immersed in paint up to one third length of
bristles and the excess paint in the brush is removed by gently pressing the bristles
against the inside surface of pot.
After the work is over, the brushes should be cleaned at once with kerosene oil.
86

87. Natural bristles Brush
Artificial bristles Brush
Larger sized bristles
87

88. Paints
 The ready mixed paints of different make and various brands are available in the
market.
 They are available in different tints and can be applied in the same form as
received.
 The ready mixed paints normally expensive and are to be used soon after opening
the sealed container otherwise solidification of base and pigment occurs due to
volatisation of vehicle and solvent.
88

89. The procedure of preparing paint from stiff paint
The sufficient stiff paint is taken in a pot. The remaining stiff paint is to be covered
or left with a layer of linseed oil.
The linseed oil which may either be raw or boiled or pale is then mixed with stiff
paint by stick.
The other ingredients of paint are then added.
If a color is required, suitable pigment is added and thoroughly mixed.
A second pot is taken and it is covered with a canvass which is tied tightly.
The mixed paint is then allowed to pass through the canvass of second pot.
The paint is now ready for use. The mixed paint may be prevented from drying by
maintaining a thin film of linseed oil or of water at top.
89

90. 90

91. 91

92. 92

93. Knotting
The process of covering or killing of all knots in woodwork with a substance through
which the resin cannot exude or come out.
Types of knotting
 Ordinary or Sized knotting
 Patent knotting
 Lime Knotting
93

94. Ordinary or Sized Knotting
This is applied in two coats.
For the first coat, the red lead ground in water and mixed with strong
glue size is used in hot condition.
This coat dries in 10 minutes and then second coat is applied. The
second coat consists of read lead ground in oil and it is thinned by
boiled oil and turpentine.
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95. Patent Knotting
This is applies in two coats.
For both coats varnish prepared by dissolving shellac in methylated spirits of wine
is used.
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96. Lime Knotting
The knot is covered by hot lime and it is left for 24 hours.
The surface is then scrapped off and then ordinary knotting is carried out.
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97. Stopping
The term stopping is used to indicate the rubbing down the surface after the first
coat of paint (primer) is applied.
The rubbing is done by means of pumice stone or glass-paper.
Before rubbing is commenced, the holes, cracks, etc. on the surface are filled with
ordinary putty.
It is adopted for superior work.
Hard stopping: Similar to ordinary stopping but incase of ordinary putty, an
admixture of one-third white lead and one-third ordinary putty is used for fillings.
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98. Coats
The paint is usually applied in 3 or 4 coats.
The first coat is known as priming coat, second one as under coat and rest are
finishing coats.
The priming coat creates a layer which provides adhesion of the point with the
surface.
Suitable material for priming coat should be used as per the surface to be painted.
The under provides the support or foundation to the finishing coat. And it also
helps to make the surface even and remove all the irregularities of the surface.
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99. 99

100. Spray Painting
Instead of the ordinary brushes, a spraying pistol may be used for painting work.
The piston works under the compressed air and the paint is thrown through the
pistol on the surface forms a thin uniform layer of paint on the surface.
Advantages over Brush painting
Speed of work
An experienced painter can create artistic patterns or designs on the surface by
spraying paints of different shades.
It is found to be economical in material and labor. The coat of spray would be
sufficient whereas ordinary brush painting would require three or four coats.
The paint is always in state of motion which ensure the proper mixing of ingredients.
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101. 101

102. 102

103. 9.4.2 Painting on Different Surfaces
The process of painting depends on the nature of of the surface to be painted.
The different surfaces to be painted are:
 New woodwork
 Repainting of old woodwork
 New ironwork and steelwork
 Repainting the old ironwork and steelwork
 Galvanized ironwork
 Metals
 Plastered Surfaces (Masonry Surfaces)
 Concrete Surfaces
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104. 104

105. New woodwork
Normally four coats of paint are required for new woodwork.
The process of painting is carried out as follows:
The surface of woodwork is prepared to receive the paint. It is important to note
that woodwork should be sufficiently seasoned and should not contain more than
15 percent moisture at the time of painting.
The surface of the woodwork is then knotted.
The priming coat is then applied on the surface of new woodwork.
The process of stopping is then carried out.
The subsequent coats of paint namely, under coats and finishing coats are then
applied on the surfaces.
Note: The extreme care should be taken to see that the finishing coat presents
smooth and even surfaces
and no brush marks are seen on the surfaces.
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106. Repainting old woodwork
 If the paint on the old woodwork has cracked or has developed blisters, it is to be
removed.
 If the surface has become greasy, it should be cleaned by rubbing down sand
paper or fine pumice stone
 The old paint can be removed by applying any one of the following three paint
solvents.
 ( methylene chloride, acetone, toluene, methanol, sodium hydroxide and
ammonia hydroxide )
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107. A solution containing 2N of caustic soda to a liter of water is prepared and used to
wash the surface. The paint dissolves and the surface becomes clean.
A mixture consisting of one part of soft soap and two parts of potash is prepared
and one part of quicklime is then added afterwards. This mixture is applied on the
surface in the hot state and allowed to stay for 24 hours. The surface is then washed
with hot water.
A mixture consisting of equal parts of washing soda and quicklime is brought to
paste form by required quantity of water. It is then is applied on the surface and
kept for about an hour. The surface is then washed with water.
After removing old paint from the surface, the woodwork is painted as in case of
painting on new woodwork.
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108. New ironwork and steelwork
The surface of iron or steel to receive the paint should be free from rust, grease,
dirt etc.
The suitable equipment such as wire brushes, scrapers, etc. are used to remove
all loose scales, marks etc. from the surface.
The water with caustic soda or lime is used to remove the grease if present.
The cleaned surface is provided with thin film of phosphoric acid. This film
protects the surface from rust and it also facilitates the adhesion of the paint.
The coats of paint are then applied.
The paint suitable for iron and steel surfaces should be selected for each coat.
The finishing coat should be applied with a great care so as to avoid brush
marks on the surface and to ensure smooth surface.
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109. Repairing the old ironwork and steelwork
Surface should be thoroughly cleaned with soap water and if grease is present lime
water is to be used.
If old paint is to be removed it can either be done by burning the paint or using any
paint solvent to dissolve the paint.
After surface is prepared, the rest is similar to that of painting on new ironwork or
steelwork.
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110. Galvanized ironwork
It is a general rule not to paint the galvanized ironwork until it has been exposed
to weather for a period of one year or so.
As the paint will not adhere to the galvanized ironwork, some treatment is given
to the surface before a priming coat is applied
However, if it is necessary to paint a new galvanized ironwork, any of the
following two solutions is applied on the surface
A solution containing 0.40 N of copper acetate to a litre of water.
A solution containing 0.13 N each of muriatic acid, copper chloride, copper
nitrate and salt ammoniac to a litre of soft water. This much quantity of solution
has coverage of 250 sq. m to 300 sq. m
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111. The solution is taken in glass vessel or earthenware vessel. After applying it, the
surface turns black and after a period of about 12 hours, the coat of paint may be
applied on the surface.
Alternately, a wash of washing soda or zinc sulphate may be given on the surface
and when it dries, a priming coat of red lead mixed with linseed oil and
turpentine may be applied on the surface.
When priming coat dries, suitable paint coats can be applied.
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112. Metals
The surface of the metal to be painted should be clean and free from dirt, grease,
etc.
Depending upon the nature of metal suitable paint is selected.
For example; priming coat for aluminum surface should be of zinc chromate and
for zinc surface it should be zinc oxide.
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113. Plastered surfaces (Masonry surfaces)
For successful painting work on cement plastered surfaces, the following points
should be carefully considered.
There is considerable moisture in newly constructed wall with cement plaster.
It is necessary to allow moisture content to escape.
Drying period depends on atmospheric condition and ventilation.
But it usually requires about 3 to 6 months for the surface to be ready to receive
paint.
The cement plaster is alkaline in nature because lime is liberated during the
hydration of cement.
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114. Hence the coats of alkali resistant primer paint should be applied or paint not
containing any oil should be used.
The different defects in cement plastered surfaces develop due to various
reasons. Such defects should be removed.
Efflorescence: Spot showing efflorescence should be brushed off. This process
should be repeated until the effects ceases.
Discoloration: Sterilize it with an antiseptic wash. The organism responsible for
discoloration are algae, mould, lichen etc.
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115. Efflorescence in cement
plastered wall.
Usual paints recommended for cement plastered surfaces are cement paints,
emulsion paints, oil paints, silicate paints.
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116. Concrete Surfaces
Cement paint is used to paint the concrete surfaces.
The paint is available in powder form and it is dissolved in water to a workable
consistency.
The paint thus prepared should be consumed in within 2 to 3 hours.
The two coats at an interval of 24 hours are just enough.
The water should be sprayed at intervals to provide curing to the painted surface.
Floor Surfaces.
The enamels are used to paint the floor surfaces.
The selected enamels should be strong to resist abrasion, moisture and alkali action.
It should also be shinning in nature and quick drying type.
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117. Defects in painting
Blistering
The defect caused by the water vapor which is trapped behind the painted surfaces.
The formation of bubbles under the film of paint occurs in this defect.
Other causes are imperfect seasoning of timber, excess oil used in final coat etc.
Bloom
In this defect, the formation of dull patches occurs on the finished/polished surface.
It is due to defect in the paint or bad ventilation.
Fading
The gradual loss of color is known as fading and it is mainly due to effect of sunlight
on pigments of paint.
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118. 118
Flaking
A small portion of painted surface is sometimes seen loose. It is known as the
flaking and is due to poor adhesion.
Flashing
sometimes the glossy patches are seen on the painted surface. This is due to poor
workmanship, cheap paint or weather action.

119. 119

120. References and sources
 Text book of Building Technology by Er. Om Prakash Giri
 Manual on Building technology by Er. Hari ram Pyakurel
 https://www.pinterest.com/
 https://sullivanengineeringllc.com/
 https://www.britannica.com/
 https://www.archute.com/
 https://mymodernmet.com/
 https://en.wikipedia.org/
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121. Any Questions?
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122. Thank You!
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