This document provides an overview of lime and various types of cement. It discusses the sources and classification of lime, as well as its uses. It also covers the composition and functions of ingredients in ordinary Portland cement. Different types of cement are described, including rapid hardening cement, low heat cement, sulphate resisting cement, and others. Key tests for cement, such as consistency, setting time, and soundness are outlined.

1. SUNDARRAJAN P
LECTURER/ CIVIL

2. UNIT I
 Introduction
 Rocks and stones
 Bricks
 Lime and pozzolanas
 Cement
 Water
 Glass
 Ceramic products

3. Lime and pozzolanas
Lime is cementing material used
since from ancient times
Some of the lime structures exist in
good condition still today
Eg. Bridges, temples, forts, palace,
dams etc.,

4. Sources of lime
 Lime is not available in nature as free state
 They are produced by burning
 Limestone
 Kankar
 Shellls of sea animals
 Burning process is known as calcination
 Limestone has great part to caco3 when burn with
fuel coal it emits co2 and cao (calcium oxide) or quick
lime

5. IS classification of lime
 Class A – eminent hydraulic lime (dome, arch,
underwater works)
 Class B – semi-hydraulic lime (masonry mortar,
concrete)
 Class C – fat lime (plastering. White washing, masonry
mortar with pozzolanic material)
 Class D – dolomite (plastering white washing)
 Class E – kankar lime (masonry mortar)
 Class F – siliceous dolomite lime (plastering)

6. Classification of lime:
❖Fat lime.
❖Hydraulic lime.
❖Poor lime.

7. Fat lime
It is also known as high calcium lime, pure lime, rich
lime, white lime.
Volume is increased about 2-2.5times when added to
water.
It have 95% of calcium oxide and 5% impurities.
Properties:
Hardens very slowly.
High degree of plasticity.
Soluble in water.
Pure white color.
Sets slowly in presence of air
Slakes vigorously.
Uses: mortar, plastering, white washing

8. Hydraulic lime.
Also called water lime
Lime containing clay with silica and alumina
It can be harden when water is added.
Slakes slowly
Muddy white and sets slow
Types of hydraulic lime.(depends of % of clay)
Feebly hydraulic lime.(5-10% clay)
Moderately hydraulic lime.(11-20% clay)
Eminently hydraulic lime.(21-30% clay)

9. Properties of hydraulic lime:
❖ Increase in percentage of clay causes slaking
difficult.
❖ If it contains 30% clay it acts as a natural cement.
❖ It can set under water whether no free
circulation of air.
❖ Not pure white color.
❖ It forms a paste with water.
Uses:
❖ Used for plaster work.

10. Poor lime:
It is also known as impure lime.
It contains more than 30% clay.
Slakes very slowly.
It does not dissolve in water, forms
thin paste
Hardens very slowly.
It makes very poor mortar.
This mortar used for temporary works.

11. Comparison between fat lime & hydraulic lime:
Sl.No Item Fat lime Hydraulic lime
1 Composition Pure carbonate if
lime & 5% clay.
Obtained from lime
stone, 5-30% ferrous
oxide.
2 Slaking
action
Slakes vigorously & 2-
2.5 times volume is
increased.
Slakes slowly. Volume
slightly increased.
3 Setting
action
It sets under air It sets underwater.
4 Hydraulicity Not possess hydraulic
property.
Possess hydraulic
property.
5 Colour Pure white. Not pure white.
6 Strength Not very strong. Very strong.
7 Uses Plastering & white
washing.
Used for preparing
mortar

12. Uses of lime
 Chemical raw material in purification of water and
waste water
 Flux in metallurgy industry
 Mortar and concrete
 Furnaces lining material
 Glass production
 Plastering of walls & ceilings
 Soil stabilization for agriculture purpose
 White wash

13. Pozzolanic material
It is a natural or artificial material
Added to lime to make it Cementous property
Common pozzolanic materials:
Surki:
Obtained by grinding of burnt bricks.
Fly ash:
It is a residue from the combustion of coal in power
stations.
It is in powdered form, it is directly used as a pozzolana.
Availability in bulk and low cost so it is used in
manufacture of cement.
It is used in large civil engineering projects.

14. Ground blast furnace:
It is a waste product obtained from the manufacture
of iron.
It is used to make durable concrete structure
combination with OPC.
Concrete made with ground blast furnace sets slowly
& having high strength than OPC concrete.
It have lower heat of hydration.
It affect the construction schedules.

15. Rise husk ash:
It generates from rice mills during milling of paddy.
RHA is a good pozzolana it can be used in special
concretes.
Rise husk also used for power generation.
Uses:
It is mixed with cement termed as ASHMENT.
Mixed with lime gives black cement.
RHC containing more than 20% lime will have acid
resisting property.

16. Advantages of addition of
pozzolana:
It improves the workability of mortar and
concrete.
Lower heat hydration.
Early setting & hardening of mortar.
Reduces the shrinkage of mortar &
concrete.
Reduces permeability of concrete.
Resistance mortar & concrete to chemical
attack.
Economical to use.

17. Cement:
Cement is manufactured by burning calcareous and
argillaceous materials at a very high temperature and
then grinding the burnt mixture to a fine powder.
Composition of OPC:
Lime 62%
Silica 22%
Alumina 5%
Calcium sulphate 4%
Iron oxide 3%
Magnesia 2%
Sulphur 1%
Alkalis 1%

18. Functions of cement ingredients:
Lime:
It is an important ingredient.
Proportion is carefully maintained.
Strength is based on lime.
Less means low strength and sets quickly
More means unsound (expand to disintegrate)
Silica:
It gives strength to concrete.
More means strength increase but setting time prolong
Alumina:
It gives quick setting property.
If excess cement become weak.

19. Calcium sulphate:
It is available in the name of gypsum.
It will increase the initial setting time of cement.
Iron oxide:
It gives color, hardness & strength.
Magnesia:
If it present small amount it gives hardness and color.
Sulphur
Correct portion
Alkalis:
It may present in small amount.
It is excess cement efflorescence causes.

20. Storage of cement:
❖ Wall, roof & floor of shed should be water proof.
❖ Small windows should be provided and kept shut.
❖ Floor should be above ground level and drainage
should be provided.
❖ For 20bags cement need 1m3 space.
❖ Storing of cement for long period should be avoided.
❖ Cement stored in bulk form should be stored in silos or
air tight containers.
❖ Storing during rainy season should be avoided.

21. Tests of cement
 Field test
 Colour
 Physical properties
 Presence of lumps
 strength
 Lab test
 Chemical composition
 Fineness
 Compressive strength
 Tensile strength
 Consistency
 Setting time
 soundness

22. Field test
Colour test
 Uniform grey colour with light greenish shade
Physical properties
 Warm and rough went felt between fingers
 Indicate adulteration when hand is inserted in bag
Presence of lumps
 Lumps indicates absorption of moisture such cement
should rejected
Float Test
 The particles of cement should flow freely in water for
sometime before it sinks
Date of Manufacturing
 It is very important to check the manufacturing date
because the strength of cement decreases with time. It's
better to use cement before 3 months from the date of
manufacturing.

23. Lab test

24. Fineness test
 To check proper grinding of cement
 Performed by IS 90 micron sieve or by blains air
permeability apparatus to determine surface area
 The cement of good quality should have less than 10%
of wt of cement particles larger than 90 µm. (micron)


25. Procedure for finding Fineness
test of cement:
 Take a sample of cement and rub the cement with your
hands. The test sample should be free of lumps.
 Now Take 100g of cement and note it as W1.
 Pour 100g of cement in 90 µm sieve and close it with the lid.
 Now place the sieve in Sieve shaking machine for two minutes.
You can also shake the sieve with your hands by Agitating the
sieve in planetary and linear movements for 15 minutes.
 Nextly, weight the residue retained on the 90 µm sieve as W2.
 Then calculate the percentage of Wt of cement-retained on
Sieve.
 Repeat the above experiment with three different samples of
cement and average the values for accurate results.

27. Chemical composition
 The ratio of the percentage of alumina to that of iron
oxide should not be less than 0.66.
 Lime Saturation Factor (LSF), i.e., the ratio of the
percentage to that of alumina, iron oxide and silica
should not be less than 0.66 and not be greater
than 1.02.
 Total sulphur content should not be greater
than 2.75%.
 Weight of insoluble residue should not be greater
than 1.50%.
 Weight of magnesia should not be greater than 5%

28. Strength test

29. Consistency test
 The Consistency of cement test is performed to
determine the amount of water content that is to be
added in cement to attain Standard consistency or
normal consistency of cement.
 Amount of water added in cement to penetrate
the Vicat plunger up to a depth of 5-7mm from the
bottom of the Vicat mould
 The Standard or Normal consistency for Ordinary
Portland cement varies between 25-35%.

30. significance
 When water is mixed with cement, it starts hydration.
 Excessive addition of water in cement results in an
increase in Water cement ratio & ultimately cement
loses its strength when it hardens.
 If Less water is added than required, Cement isn’t
properly hydrated and results in loss of strength.

31. procedure
 Take 400g of cement and place it in a bowl or tray.
 Now Assume standard consistency of water is 25% and
add the same quantity of water in cement and mix it.
 Mix the paste thoroughly within 3-5 minutes. The time
taken to obtain cement paste after adding water is
called gauging time.
 Now fill the paste in Vicat mould correctly any
excessive paste remained on Vicat mould is taken off
by using a trowel.
 Release the Plunger and allow it to sink into the test
mould.
 Note down the penetration of the plunger from the
bottom of mould indicated on the scale.
 Repeat the same experiment by adding different
percentages of water until the reading is in between
5-7mm on the Vicat apparatus scale.

33. Setting time test
Initial Setting time of Cement:-
 The time to which cement can be moulded in any
desired shape without losing it strength is called Initial
setting time of cement.
 For Ordinary Portland Cement, The initial Setting Time is
30 minutes.
Final setting time of Cement:-
 The time at which cement completely loses its
plasticity and became hard is a final setting time of
cement.
 For Ordinary Portland Cement, The Final Setting Time is
600 minutes (10hrs).

34. procedure
 Take 400g of cement and place it in a bowl or tray.
 Now add water of Start the stopwatch at the moment
water is added to the cement. Water of quantity
0.85P.times (Where P is the Standard consistency of
cement) is considered.
 Now fill the mix in Vicat mould. If any excessive paste
remained on Vicat mould is taken off by using a trowel.
 Release the needle and allow it to sink into the test
mould.
 Note down the penetration of the plunger from the
bottom of mould indicated on the scale.
 Repeat the same experiment at different positions on the
mould until the plunger should stop penetrating 5 from
the bottom of the mould.
 The time period elapsed between the moment water is
added to the cement and the time, the needle fails to
penetrate the mould of 5mm when measured from the
bottom of the mould, is the initial setting time of cement.

36. Soundness test
 Soundness test of cement is done to ensure that
cement doesn’t show any expansion after hardening
and to find out the uncombined lime in cement
(excess lime). In simple words, this test is conducted to
check “unsoundness of cement”

37. procedure
 Before Performing the test, calculate the standard
consistency of cement to find out the water required to
obtain the normal consistency(P).
 Now add 0.78 times of water to the cement to give a
paste of standard consistency (0.78P).
 Lightly apply oil to the Lechatelier mould and place it on
a glass plate.
 Now pour the cement paste into mould and close the
mould using lightly oiled glass plate and to avoid
misplacement place a weight on it.
 Then, submerge the whole assembly for 24Hrs in water
bath at a temperature of 270C
 Remove the entire apparatus from water and then
calculate the distance separating two indicator points
using measuring scale and note it as L1.
 Again submerge the whole assembly in a water bath at a
temperature of boiling point for 3hours.
 After completion of 3 hours remove the assembly from
the bath and measure the distance between two
indicator points and note it as L2.

38. Expansion Limits
Ordinary Portland
cement
[OPC] 33 Grade, 43
Grade, 53 grade
10mm

39. Types of cement

40. Ordinary Portland Cement
(OPC):
 This is the most common type of cement which is
extensively used.
 It has good resistance to cracking and dry shrinkage
but less resistance to chemical attack.
 OPC is not suitable for the construction work which is
exposed to sulphates in the soil.
 Ordinary Portland cement is available in following
types 33 grade, 43 grade & 53 grade.
 The grade represents the strength of cement at
28days. 33grade = 33N/mm2

41. Rapid Hardening cement:
 Rapid hardening cement is very similar to ordinary
Portland cement (OPC).
 The early strength is achieved by adding excessive C3S
in the mix and by lowering the C2S content in the
cement.
 Ex. Pavements, busiest roadways
 The strength of Rapid Hardening cement at age of 3
days is almost same as the 7 days strength of Ordinary
Portland cement.
 It requires same water-cement ratio as OPC.
 This type of cement is not used for massive concrete
constructions

42. Low heat portland cement
 This type of cement is manufactured by lowering the
C3S content and increasing the C2S content.
 It possesses less compressive strength than ordinary
Portland cement.
 It has less lime content than OPC.
 This type of cement is mostly used in the construction
of retaining walls and it is strictly not suitable for thin
concrete structures.

43. Sulphate Resisting Portland
Cement:
 It is manufactured by keeping the percentage of C3A
below 5%.
 This type of cement is used where the structure is
prone to severe sulphate attacks(alkaline conditions)
such as construction in the foundation of soil, marine
conditions, sewage treatment tanks

44. High alumina Cement
 This type of cement has rich alumina content about
35% which helps in gaining ultimate high strength
within a short period.
 This type of cement is used where a structure is
subjected to the action of sea water, chemical plants
and furnaces.

45. Blast furnace slag cement
 This type of cement is cheaper than Ordinary Portland
cement.
 it is manufactured by inter grinding of OPC clinker
and blast furnace slag.
 Blast furnace slag cement develops low heat of
hydration and has less early strength.
Coloured Cement:-
 This type of cement is also known as Colcrete.
 It is manufactured by adding coloring pigment to the
OPC.
 it is used in joining tiles.

46. Pozzolana cement
 The pozzolana is a material which is formed due to the
volcanic eruptions.
 It is a siliceous material having about 80% clay in it.
 Pozzolana cement is manufactured by mixing 30% of
pozzolana to Ordinary Portland cement clinkers.
 This type of cement is used in construction of dams
and weirs.

47. Air-entraining cement:-
 This type of cement is manufactured by adding 0.025–
0.1% of air entraining agents to the ordinary Portland
cement clinker.
 Air entraining agents are generally made up of wood
resins, calcium agents, vegetable oils and animal fats.

48. Hydrophobic cement:-
 This type of cement is manufactured by grinding
ordinary Portland cement clinker with stearic acid.
 These acids forms as a water repellent film around the
cement particle which increases the shelf life of
cement.
 The formed around each grain of cement reduces the
rate of deterioration of the cement during long
storage, transport, or under unfavourable conditions.
 The film is broken out when the cement and
aggregate are mixed together at the mixer exposing
the cement particles for normal hydration.

49. Expansive cement
 This type of cement is manufactured by adding
stabilizer which stabilizes the cement to expand.
 This can be achieved by adding 8-20% of
sulphoaluminate & 15% of stabilizer to the ordinary
Portland cement clinker.
 Concrete made up of OPC shrinks while setting due to
loss of free water. Concrete also shrinks continuously
for a long time.
 Cement used for grouting should not shrink or change
volume for this, we use expansive cement. the
expansive cement doesn’t show any volume change
after hardening.

50. White Cement
 This type of cement is obtained by lowering the iron
oxide content in the Ordinary Portland cement.
 The strength and durability is same as OPC.
 This type of cement is used for joining tiles and other
interior works.
Waterproof portland cement:-
 This type of cement is manufactured by adding small
percentages of metal sereates in OPC during grinding.
 This type of cement is used in foundations, water tanks
& other water retaining structures.

51. Oil-well Cement
 In order to extract oil from the stratified sedimentary
rocks, Oil wells are dug to a greater depth.
 For safe pumping out of extracted oil steel casing is
inserted.
 It is likely that if oil is struck, oil or gas may escape
through the space between the rock formation and
steel casing.
 To fill this space Oil well cement is used.
 Oil well cement is manufactured by adding retarders
(Starches or cellular products) to Ordinary Portland
cement.

52. Admixture
 Chemicals added along with concrete ingredients
(fine aggregate, coarse aggregate, cement and
water) to alter the properties of fresh and harden
concrete.

53. TYPES
Sl.no. Admixture Functions
1. Accelerators Rapid gain of strength
2. Retarders Delay setting
3. Water reducing
accelerator
Inc. workability with gain of faster
strength
4. Water reducing
retarders
Inc. workability & delay setting
5. Water proofers Reduce permeability, prevent
water entering
6. Air entraining Entrainment of air into concrete
7. Plasticizers Inc. workability
8. Super plasticizers Greatly inc. workability

54. Admixture functions & uses
 Accelerate initial
setting time
 Retard initial setting
time
 Inc. strength
 Inc. durability
 Improve workability
 Reduce heat of
evolution
 Improve pumpability
and penetration
 Reduce segregation
 Inc. bond b/w old and
new concrete
 Inc. resistance to
chemical attack
 Produce non skid
surface
 Dec. wt. of concrete
 Dec. capillarity flow
 Produce colored
concrete

55. water
 Water is one of the most important elements in
construction and is required for the preparation of
mortar, mixing of cement concrete and for curing
work etc.
 The quality of water used has a direct impact on the
strength of the motor and cement concrete in the
construction work.
 The water used for curing and mixing must be free
from high quantities of alkalis, acid, oils, salt, sugar,
organic materials, vegetable growth, etc that might
be deleterious to bricks, concrete or iron.

56. Frequency of testing of water
 Water from each source shall be got tested before the
commencement of work and thereafter once in every
three months till the completion of the work.
 Water from municipal source need to be tested only
once in six months.
 Number of tests for each source shall be three.

57. Water Quality Tests for Concrete
Construction
 pH value test
 Limits of acidity test
 Limits of alkalinity test
 Percentage of solids
 Chlorides
 Suspended matter
 Sulphates
 Inorganic solids
 Organic solids

58. pH
 a) Limits of acidity: To neutralize 100ml sample of
water, using phenolphthalein as an indicator, it should
not require more than 5ml of 0.02 normal NaOH. The
details of test shall be as given in IS 3025 (Para 22).
 b) Limits of alkalinity: To neutralize 100ml sample of
water, using mixed indicator, it should not require
more than 25ml of 0.02 normal H2SO4. The details of
tests shall be as given in IS 3025 (Para 23).

59. Percentage of solids
Types of solids Limits
Organic solids 200 mg/liter
Inorganic solids 3000 mg/liter
Sulphates 400 mg/liter
Chlorides
2000 mg/liter for
concrete not containing
embedded steel, and
500 mg/liter for
reinforced concrete
work
Suspended matter 2000 mg/liter

60. Sea water for construction
 Not used
 It accelerates early strength of concrete but reduce
final strength by 10 to 15 %

61. GLASS
 Not soluble in water
 Unaffected by acid
 Transparent
 Hard
 Brittle

63. Glass
It is a mixture of metallic silicates and alkali metal.
Constituents of glass:
Silica:
➢ Principle constituent.
➢ It could be fused at very high temperature.
➢ It give good glass on cooling.
Sodium or potassium carbonate:
➢ It is an alkaline material.
➢ It is added suitable proportion to reduce melting point of
silica.

64. Lime:
➢ It is added in the form of chalk.
➢ It gives durability.
➢ Lead oxide also added.
➢ It makes glass bright & shining.
Manganese dioxide:
➢ It is added suitable proportion to correct color.
➢ It is also called “Glass maker” soap.
Cullet:
➢ It is the old broken glass of same type.
➢ It is added small quantity.
Coloring substance:
➢ Coloring substances are cobalt, nickel and
manganese oxide.

65. Classification glass:
Soda-lime glass:
➢ Cheapest quality of glass.
➢ It is manufactured by heating and melting & fusing
sodium & calcium silicates.
➢ Example is door & window glass.
Flint glass:
➢ It contains varying proportion of lead oxide.
➢ Lead provides high polish to glass.
Uses:
➢ Electric lamps, thermometers, electron tubes, laboratory
apparatus.

66. Heat resistant glass:
Manufactured Elimination of basic oxides and inclusion of
boron oxide.
Melting point is very high. It is heated in the electric arc.
Used for cooking utensiles, laboratory wares.
Types of glass:
Gluted glass:
In this glass corrugation is provided one side.
Uses:
Used for sky light roof, windows of railway stations &
factories.

67. Ground glass:
➢ It is manufactured by melting powdered glass.
Uses:
➢ Window panels & bathroom ventilators.
Wired glass:
➢ It is a glass with wire.
➢ It is known as reinforced glass.
uses:
➢ Skylight roofs & fire resistant doors, windows.

68. Safety glass:
➢ It is produced by sandwiching sheet of celluloid or
transparent plastic between two sheets of glass.
Bullet proof glass:
➢ It is made of several layers of plate glass.
➢ Special care taken for heating and cooling.
Uses:
➢ Cashier booths, bank teller, jewellery stores.
Foam glass:
➢ It is prepared from powdered glass & added desired
quantity of carbon.
➢ Uses:
➢ Sound & heat insulation.

69. Glass blocks:
➢ These blocks are hollow transparent units.
Uses:
➢ Used for partition walls.
Soluble glass:
➢ Prepared by melting quartz, sand, grinding thoroughly
mixing it with soda ash, sodium sulphate & potassium
carbonate.
Uses:
➢ Used for acid resistant cement.
UV ray glass:
➢ It transmites UV rays effectively.
➢ Made from iron, titanium and chrome.
➢ Used for windows of schools & hospitals.

70. Structural glass:
➢ It is available in the form of square blocks, tiles in
thickness varying from 5-30mm.
➢ Used for pavement tiles, roof covering etc.
Sheet glass:
➢ Thickness varying from 1.5-5mm & sizes 1.5 x 5m.
Plate glass:
➢ It is thicker than sheet glass.
➢ Thickness is 5-25mm & size 2.75m x 0.9m
Uses:
➢ Wind screens of motor vehicle, car sky lights.

71. Uses in building:
✓ Fibre glass with plastic can be used for furniture, cars
etc.
✓ Manufacture of riffle barrel.
✓ Used in the noses of diving vehicles.
✓ Optical glass used in astronomy & bacteriology.
✓ Used for glass lining.
✓ Hollow blocks.
✓ Color changing glass.

72. Ceramic products
 Art of making objects with clay and similar materials
by treating with fire
Earthenware:
It is a ordinary clay products burnt at low temperature
Low mechanical strength
Porous and soft
When glazed it becomes water tight
Used as pots, drain pipes, electrical cable conducts

73. Stoneware:
Made from refractory clays mixed with grounded
pottery & stone.
This mixture is burnt high temperature & cooled down
slowly.
It have more strength and compact than
earthenware.
When glazed impervious to water
Good stoneware giving clear ringing sound.
It is strong, durable & resistant to corrosive fluids.
Cleaned easily.
Stoneware articles are wash basin, sewer pipes, water
closets etc…

74. Porcelain:
It indicates a fine earthenware which is shine, thin and
semi transparent.
Color is white so it is called whiteware.
Hard, brittle and non porous
It is prepared from clay, felsper, quartz and minerals.
It is used as an electric insulator, storage vessels,
sanitary wares, crucibles etc..
Terracotta:
High quality earthenware & used for ornamentation of
buildings.
It is soft scratched by knife.

75. Glazing:
Process of forming transparent film over the surface of
bricks, tiles by burning at high temerature
Thickness about 0.1mm-0.2mm.
Uses:
Improve appearance.
Makes articles durable & impervious.
Gives decorative effect.
Protect articles from atmosphere & chemical actions.
Provide smooth surface.
Tiles:
Thin product of ceramic clay.
Used in buildings, flooring, paving, etc….

76. Types of tiles:
Burnt clay tiles.
Drain tiles
Floor tiles.
Roof tiles.
Ceramic tiles.
Porcelain tiles.
Glazed ceramic tiles.
Fully vitrified tiles.

77. Roof tiles:
It is made from brick earth.
This tiles are used for covering the pitched roof.
Types of roofing tiles:
Curved tiles
✓Pot tiles
✓Pan tiles
Interlocking tiles
Flat tiles

78. Pot tiles:
It is also known as country tiles.
Made by manually with the help of potter’s wheel.

79. Pan tiles:
It is less curved than pot tiles but stronger than pot tiles.
It is moulded flat first & bend in another mould.

80. Interlocking tiles:
These are made flat with surface corrugations.
They interlock at sides with each other.

81. Flat tiles:
It have two projections at the top end.
The projections help to hung the tiles on the truss
permanenetly

82. Floor and wall tiles:
Glazed ceramic tiles:
Made from china clay or concrete.
Top surface is glazed.
Bottom surface is left unglazed to adhere to surface
Fully vetrified tiles:
It can be either glazed or unglazed.
Low water absorption.(<5%)
Clay terracing tiles:
It is a finishing layer of open tiles used as weathering tiles
It is provided with double or single layer.
It reduce the weathering effects.

83. Sanitary appliances:
Wash basin:
❖ Made from porcelain.
❖ Sometimes made from porcelain enamelled cast iron.
❖ Available in different shapes and sizes.

84. Sinks:
❖ These are made from glazed fire clay.
❖ Used in kitchen or laboratory.

85. Bath tub:
❖Made up of terrazzo or marble slabs.

86. Water closets:
Made up of porcelain.
Types:
Indian type, European type, Anglo-Indian type.
Urinals:
Made from enamelled fire clay.
Types:
Bowl type, Stall type.

87. Flushing cisterns.
Made up of porcelain.
Types are valveless siphonic type, valve fittedsiphonic
type