1. Thermal & Sound Insulation
The use of insulation and prevention of sound transmission.

2. How Heat Is Transmitted
Insert 14-4 conduction
Conduction: the transmission of heat from one molecule to another within a material or from one material to another when they are held in direct contact.

3. Convection: the transfer of heat by another agent, such as air or water.
Convection Currents: the flow of air that is created within the space.
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4. Radiation: the transmission of heat through a wave motion, similar to the way light is transmitted.
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5. Thermal Insulation Facts
Fibrous materials are generally good insulators
Commercial insulation materials are made of:
Glass fibers
Glass foam
Mineral fibers
Organic fibers
Foamed plastic

6. Characteristics of a good insulation material:
fireproof
vermin proof
moisture proof
resistant to any physical change that would reduce its effectiveness against heat flow
Selection of insulation is based on:
Initial cost
Effectiveness
Durability
Adaptation of its form to that of the construction and installation methods

7. Heat Loss Coefficients
British Thermal Unit: Btu, the amount of heat needed to raise the temperature of 1 pound of water to 1 degree Fahrenheit.
Coefficient of Thermal Conductivity: k, the amount of heat, in Btu’s, transferred in one hour through 1 sq. ft. of a given material that is 1” thick and has a temperature difference between its surfaces of 1 degree Fahrenheit.
Conductance: C, the amount of heat that will flow through the material in 1 hour / sq. ft. of surface with a 1 degree Fahrenheit of temperature difference.
Resistance: R, the opposite of conductivity or conductance. A good insulation material will have a high R- value.
Total Heat Transmission: U, represents in Btu / sq. ft. / hour with 1 degree temperature difference for a structure which may consist of several materials or spaces.

8. Insert fig. 14-8 Map insulation zones for different parts of the U.S.
R-values that are recommended by the U.S. Department of Energy.

9. Types of Insulation
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10. Flexible Insulation Insert fig. 14-11 Insert fig. 14-14 2 types
Blanket: made of loosely felted mats of mineral or vegetable fibers. Generally furnished in rolls or strips of convenient lengths and various widths. Thicknesses vary from ¾” to 12”.
Batt: Thicknesses range from 3 ½” to 12”. Generally available in widths of 15”, 23”, 24” or 48”. Available with a single flanged cover or with both sides uncovered.
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11. Loose Fill Insulation: Composed of various materials in bulk form and supplied in bags or bales. It may be poured or blown.
Rigid Insulation: Used mostly in residential construction. Made by reducing fibers to a pulp and then made into a low density board.
Reflective Insulation: Usually a metal foil or foil-surfaced material. The # of reflecting surfaces determines its insulating value.
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12. Where to Insulate
Heated areas, especially in cold climates should be surrounded with insulation.
Attics
Crawl spaces
Basements
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13. Condensation Water Vapor Dew Point Always present in the air
Penetrates wood, stone, concrete
Warm, moisture laden air within a heated building forms a vapor pressure which constantly seeks to escape and mix with the colder, drier outside air
Comes from cooking, bathing, clothes washing and drying and by humidifiers
Dew Point
The temperature at which the air is completely saturated with moisture
Any lowering of the air temperature will cause condensation
Moisture can cause deterioration of siding and paint and can also make surfaces wet

14. Vapor Barriers
A membrane through which water vapor cannot readily pass
Protects ceilings, walls, and floors
3 types: asphalt-coated paper, aluminum foil, and polyethylene films
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15. Safety with Insulation
The Occupational Safety and Health Act (OSHA) does not have specific recommendations for working with fiberglass. Installing insulation is not particularly hazardous. However, it has proposed a permissible exposure limit (PEL). The American Conference of Governmental Hygienists has suggested limits. They recommend the following practices:
Wear loose clothing. Long sleeved shirts or blouses loose at the neck and wrists, caps and long trousers will prevent most fibers from coming in contact with the skin. Loose clothing will prevent chafing where fibers do contact skin. Gloves may be recommended in some circumstances.
Protect eyes. Use goggles or safety glasses with side shields when applying fiberglass materials overhead or where loose particles or fibers may get into the eyes.

16. Insert fig. 14-38 (top) Wear a mask covering the nose and mouth.
Don’t rub or scratch the skin
Wash work clothes separately
Dispose of scrap materials
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17. Acoustical Terms
Sound: a vibration or wave motion that can be heard, reaches the ear through air, the air vibrates back and forth in tiny molecular motions of high and low pressure
Decibel: the unit of measurement used to indicate the loudness or intensity of sound; comparable to the “degree” as a measurement of heat or cold
Reverberation Sounds: airborne sounds which continue after the actual source has ceased, caused by reflections from floors, walls and ceilings
Frequency: rate at which sound energized air molecules vibrate
Impact Sounds: sounds that are carried through the building by the vibrations of the structural materials themselves
Masking Sounds: normal sounds within habitable rooms which tend to “mask” some of the external sounds entering the room

18. Decibels Reduction: expression used to indicate the sound insulating properties of a wall or floor panel
Sound Transmission Loss: STL, the number of decibels which sound loses when transmitted through a wall or floor
Sound Absorption: capacity of a material or object to reduce sound waves by absorbing them, these sounds are otherwise reflected and cause excessive reverberation and build up of intensity within that area
Noise Reduction Coefficient: NRC, the sound absorption of acoustical materials is expressed as the average percentage absorption at the four frequencies which are representative of most household noises, these frequencies are 250, 500, 1000, and 2000 cycles/second
Sound Transmission Class: STC, single number which represents the minimum performance of a wall or floor at all frequencies, the higher the STC number, the more efficient the wall or floor will be in reducing sound transmission.

19. Sound Intensity Threshold of Audibility Threshold of Pain
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20. Wall Constructions
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