Three ways of heat transfer:
1. Conduction – the inside of a concrete wall which has one side exposed to outside winter temperatures feels cold to the touch. Heat is being conducted from the side of higher temperature to that lower temperature.
2. Radiation – from this point, it is transferred to the outside air by radiation.
3. Convection – when air is heated, it expands and begins to circulate, during the circulation it comes in contact with cooler surface, some of its heat is given up to them. It is therefore important to try to prevent air currents from being set up in the walls and ceiling of our buildings.
Kinds of Thermal Insulation:
1. Loose Fill:
a. fibrous type – made from mineral woolrock wool, glass wool, or slag wool – or vegetable fiber – usually wood fiber.
b. Granular insulation – made from expanded minerals such as perlite and vermaculite or from ground vegetable matter such as granulated coork.
c. Fibrous loose fill – used to insulate walls of buildings that have been built without insulation.
d. Granules – are graded into four sizes, 1, (3/8 in. to no. 16 sieve) and sizes 2 (no. 4 to no. 30 sieve) used as loose-fill insulation for sidewalls and ceilings over suspended ceilings, between wood sleepers over a concrete floor slab, as fill for the cores of concrete blocks, and sizes 3 (no. 8 to no. 100 sieve) size 4 (no. 16 to 100 sieve).
2. Blanket Insulation – made from some fibrous materials such as mineral wool, wood fiber, cotton fiber, or animal hair, manufactured in the form of a mat, 16, 20 or 24 in. width, in 8 ft. lengths or put up in rolls of from 40 to 100 linear feet, with controlled thickness of 1, ½, 2, 3 and 4 inches.
3. Batts – similar to blankets but they are restricted to 48 inches in long or less they are always covered with paper, and made especially for installation between stud spacings.
4. Structural Insulation Board – made from organic fiber-wood, cane, straw or cork. The wood and cane raw material is first pulped, after which it is treated with water proofing chemicals.
a. Strawboard – made from carefully selected straw, fused under heat and pressure into a panel 2 inches thick and 4 ft. wide.
b. Corkboard – made from granulated cork mixed with resin and pressed into sheets of several thickness, depending on the use to which they will be put.
5. Block or Rigid Slab Insulation – type of insulation is so called because the units are relatively stiff and inelastic. In most cases inorganic materials are used in their manufactures.
6. Reflective Insulation – made from such materials as aluminum or copper foil or sheet metal, with bright surfaces that reflect heat rather than absorbing it.
7. Foamed-In-Place Insulation – this is polyurethane product made by combining a polyisocyanate and a polyester resin.
8. Sprayed-on-Insulations – materials used are polyurethane foam asbestos fiber mixed with inorganic binders, vermiculite aggregate with a binder such as Portland cement or gypsum and perlite aggregate using gypsum as binders.
9. Corrugated Insulation – usually made from paper foamed into shapes that produce enclosed air pockets. One type is produced by shaping heavy paper into a series of small regular semicircular corrugations and covering a both sides with a sheet of flat paper to give strength and produce the air pockets.
BUILDING PROTECTION
Waterproofing – a method of protecting surfaces against the destructive effects of water
Damp-Proofing – protection from the outside is provided by water repellent materials which turn water aside and force it to return to the earth.
Soil Poisoning – it is important to poison the soil against anay in order to stop the anay from infesting the main posts, walls and flooring.
Wood Preservative – a chemical liquid painted and applied to lumber to preserve it for years. It protects wood against powder post beatles (buk-bok), powder post termite (unos), decay causing fungi such as sap stain and dry rot.
Fire- Proofing – a clear liquid applied easily on wood, plywood, lumber and other board that retains the natural beauty, gives added strength and protects materials against fire, weather, decay, insects and warping.
Ratproofing – a method of protecting rooms against the intrusion of rats and other small destructive animals from gnawing the wooden parts of the house, habitating on ceilings and floors of houses and buildings.
Rustproofing – a method of protecting the ferrous materials like steel, iron from rusting or corrosion.
Thoroseal – a cement-based, heavy-duty, easy to apply, water proof sealant and coating. Thoroseal is ideal for basement walls.
Vapor barriers – are materials which effectively retard or stop the flow of water vapor and normally are produced in sheets or thin layers.
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