thermal insulating material presentation

1. THERMAL INSULATING MATERIALS
NAME: SHAH DEVANSHI S.
DIVISION:B
ENROLLMENT NO.: 143561050056
SUBJECT: BUILDING CONSTRUCTION

2. INTRODUCTION
A Residential building should be comfortable, pleasant and healthy to live and work in.
The term building insulation refers broadly to a material that is added in a building for comfort and energy efficiency .
Insulation includes:
thermal insulation for reducing the rate of heat transfer
Acoustic insulation for reducing the intensity of sound
Fire insulation and impact insulation for reduction of vibrations caused by industrial applications.
THERMAL INSULATION:
Heat is a form of energy and always flows from warmer to a cooler area i.e., it flows out of the building in the winter and
into the building in the summer. The transfer of heat due to the difference in indoor and outdoor temperature is partially
resisted by any wall, roof or floor separating such areas. Insulation is used to further reduce this unwanted heat loss or
gain and keep the building cool in the summer and warm in winter. Thus, insulation provides comfort for its occupants
and decreases the energy requirement of heating and cooling systems. The insulation materials used for this purpose
are :
• Cellulose
• Fiber glass
• Rock wool
• polystyrene
• Urethane foam
• vermiculite

3. HEAT TRANSFER FUNDAMENTALS
Heat energy is transferred by three basic modes.
All heat applications involve each mode to a greater or lesser degree.
• Conduction
• Convection
• Radiation
All the objects which are above absolute zero temperature radiate infrared energy, and transfer heat by conduction or
convection.
HEAT OR THERMAL CONDUCTION:
It is the transfer of heat energy through a solid material, from a region of higher temperature to a region of lower
temperature, and acts to equalize temperature differences. It is also described as heat energy flow from one material to
another by direct contact
HEAT CONVECTION:
The heat energy is transferred by circulation and diffusion of the heated media. It is the most common method of heating
fluids or gases. In buildings, heat transfer by convection occurs at the surfaces of the walls, floors and roofs when the
surface is either colder or warmer than the adjacent air. Typical convection heating applications include air heating, gas
heating and comfort air heating.
THERMAL RADIATION:
The transfer of heat energy by electromagnetic waves and is very different from conduction and convection. Conduction
and convection take place when material being heated is in direct contact with the heat source. In infrared heating there
is no direct contact with heat source, they flow in straight lines from space and does not produce heat energy until
absorbed. The converted heat energy is then transferred in the material by conduction and convection.

4. REQUIREMENTS OF THERMAL INSULALING MATERIALS:
In addition, to the thermal insulating properties a material should have the following characteristics for specific
applications:
POOR ABSORBENT OF MOISTURE:
Moisture appreciably reduces the thermal insulation properties of most of the materials. Therefore, insulation material
should be poor absorbent of moisture.
ADEQUATE STRUCTURAL STRENGTH:
Generally, higher void content which increases the insulating properties reduces structural strength. In the situations
where installed insulation material must bridge over a discontinuity in its support, the breaking load is an important
consideration. Compressive strength is important if the insulation must support a load or withstand mechanical abuse
without crushing.
ADEQUATE CHEMICAL RESISTANCE:
Alkalinity, is an important property when corrosive atmosphere are present. Potential fire hazards exist in areas where
volatile chemicals are present.
ADEQUATE FIRE RESISTANCE:
For insulating material its flame spread and smoke development ratings should be considered. Many porous insulating
material have good fire resisting properties. Toxicity must be considered in potential fire hazard areas.
LOW COEFFICIENT OF EXPANSION AND CONTRACTION:
These factors enter into the design of expansion /contraction joints and the use of multiple layer insulation application.
STABILITY AGAINST ENVIRONMENTAL INFLUENCES :
Resistance to ultraviolet light is an important consideration in outdoors applications.
SHRINKAGE :
It is important in application involving cements and mastics
ECONOMICAL AND EASE OF INTALLATION :
The cost of insulation is generally estimated taking in to account its durability and effectiveness and ease of installation.

5. CELLULOSE:
Cellulose is the structural component of the primary cell wall of green plants. for industrial use, it is mainly obtained from
wood pulp and cotton
• cellulose is the major constituent of paper, card board and the textile made from cotton.
• for insulation it is made by shredding and pulverizing waste paper and mixing it with dry chemicals like borax, boric
acid, aluminum sulphate, etc..
• insulation is used as loose fill in the insulation of ceiling, floors foundation and wall of new and retro fits residential
and commercial building.
• wet spray cellulose insulation is applied with small quantity of water to help cellulose binds to the surface and to make
it more resistant to settling.
• spray application provides better protection against air in filtration and improve wall rigidity.
ADVANTAGES:
1. Cellulose insulation is environmental friendly and it has less risk to install.
2. Cellulose loose insulation fills the wall cavity better the panels.
3. It has class I fire safety rating.
4. It has not made from chemicals with high toxicity .
DISADVANTAGE:
1. it does not seal bypasses as well as closed-cell foams do.
2. it may absorb moisture.
3. in case of large thickness, its weight may cause ceilings to sag. It may settle overtime, loosing some of its
effectiveness.

6. GLASS WOOL
• Glass wool is also known as fiber glass.
• Fiber glass consist of inorganic mineral base and made into glass wool by different processes.
• It is made by mixing the glass raw material in solid form and melting in a furnace .The molten glass is extruded to the
bushing to be formed into fiber. The fiber are then coated with phenolic resin binder. The fibre then passes through
an oven to cure and set the resin. The fiber is then cut and trimmed to desirable sizes
• Glass fiber are useful because of their high ratio of surface area to weight
• The increased surface area makes them much more susceptible to chemical attack .
• By trapping air with in them, blocks of glass fiber make good thermal insulation, with a thermal conductivity.
• Fibrous glass is neutral
• The product is known combustible an also has good sound absorption characteristics.
• Glass fibers may be used as loose fill in the cavities or in the form of mats, felts and board.
• Fiber glass is used for insulation of walls ceilings and floor of new residential and commercial building or retrofit
application.

7. Rock wool
• Rock wool , also known as mineral wool or mineral fibers, is a fibrous material.
• It is made from molten rock such as basalt, dolerite; iron ore blast furnace slag or recycled glass.
• The mineral is melted at very high temperature in a reverberatory furnace and then draw into thin fibers.
• The fibers are coated with oil and phenolic resin to make them water repellent.
• It has good sound absorption characteristics, highly resistant to fire and attack by vermin, insects , etc.
• It clumps and losses effectiveness when moist or wet, but does not absorb much moisture, and regains effectiveness
once dried.
• These fibers can be used as loose fill material and also in form of boards, felts and mats.
• Its upper temperature limits can reach 1038 C.
• The material which has a practically neutral pH, is noncombustible.

8. Polystyrene
• Pure polystyrene is brittle, but formed resins are generally combined with elastomers to produce a flexible cellular
material
• Available in pre- formed shapes and sheets, elastomeric insulations posses good cutting characteristics and low water
and moisture permeability.
• Polystyrene forms are good thermal insulations.
• They are used as building insulation material and also for nonweight bearing architectural ornamental pillars.
• They are two types of polystyrene foams:
1. Expanded polystyrene foam: EPS is usually white and made of expanded polystyrene beads.
2. Extruded polystyrene foam: Extruded polystyrene foam has air inclusions which gives it moderate flexibility, a low
density and a low thermal conductivity. Foamed between two sheets of paper, it makes a more uniform substitute for
corrugated cardboard.
• Polystyrene’s greenest feature is the ease with which it can be recycled.
• During construction these rigid boards are concealed inside wall, ceiling, or roof areas.

9. SELECTION OF INSULATING MATERIAL
The selection of insulation is based on the following factors:
• prevailing climate
• Ease of installation, e.g., some materials cannot be installed due to tissues of accessibility or toxicity
• Durability of installation is governed by its resistance of compression, moisture, degradation.
• Cost of insulation is generally related to its durability and effectiveness.
• The mode of heat transfer governs the effectiveness of insulation.
• The orientation of the surface and direction of heat flow determine the effectiveness of a radiant barrier. Radiant
barriers will work best at stopping.
• environmental impact and sustainability- Usually the combination of material is required to achieve an optimum
solution for insulating a building over a range of climatic condition.

10. STRUCTURAL CLASSIFICATION:
FIBROUS INSULATION:
Fibrous insulation materials are composed of small diameter fibers which finely divide the air
spaces. The fibers may be perpendicular or parallel to the surface being insulated, and they may or may not be bonded
together. In this type of insulation silica, rock wool, slag wool and alumina silica fibers are used. The most widely used
are glass wool and mineral wool.
CELLULAR INSULATION:
This type of insulation is composed of small individual cell separated from each other. The
cellular material maybe glass or foamed plastic such ass Polystyrene (closed cell), Polyurethane, Polyisocyanurate,
Polyolefin and elastomeric
GRANULAR INSULATION:
This type of Insulation is composed of small nodules which contain voids or hollow spaces.
This type may be produced ass a loose or pourable material, or combined with a binder and fibers to make a rigid
insulation. Examples of these insulations are calcium silicate, expanded vermiculite,perlite,cellulose, diatomaceous earth
and expanded polystyrene.

11. NON-STRUCTURAL CLASSIFICATION:
Insulation is produced in variety of forms suitable for specific functions and applications:
PRE-CUT OR BATT INSULATION:
This is the most common type of insulation. The Batts are available in a variety of
lengths, widths and R-values, with and without facing. Faced panels are used in exterior walls, ceilings, floors. The facing
material usually severs as a vapor retarder and makes handling and attachment easier to install.
BLANKET INSULATION:
Only fibrous insulations are produced in the form of flexible blankets. Flexible blankets in the
form of panels or rolls are available in widths suited to standard wall, floor, and framing spaces.
LOOSE-FILL INSULATION:
Loose-fill materials are ideal for the use in hard to reach areas because they conform to
space and fill in nooks and crannies. Many types are made of recycled material and are relatively inexpensive. Blown-in,
loose fill insulation includes loose fibers or fiber pellets that are blown into building cavities using special pneumatic
equipment.
FOAMED-IN-PLACE:
poured or froth foam maybe used to fill irregular areas and voids, and spray is used for flat
surfaces.

12. NON-STRUCTURAL CLASSIFICATION:
RIGID INSULATION:
All the three types of insulation namely cellulose, granular and fibrous insulation can be produced in
the form of rigid board, blocks, sheets and other pre-formed shapes. It is made from fibrous material that are pressed
into sheets. These provide thermal and acoustical insulation, strength with low weight, and coverage with few heat loss
paths.
STRUCTURAL INSULATED PANELS:
Structural insulated panels, are also called stressed skin wall, can be used for
ceilings, floors, walls, and roofs. The panels usually consists of ply board, oriented strained board or dry wall glued. The
advantage of structural insulated panels are
1. They are strong and can support some load
2. They are amenable to faster construction and require less timber.
3. They may also provide acoustic insulation.
4. They are not energy intensive.
INSULATING AND FINISHING CEMENTS:
Insulating and finishing cements are reduced from fibrous and granular
insulating materials and cement.