Definition for word: Insulation

Thermal insulation in buildings is an important factor to achieving thermal comfort for its occupants. Insulation reduces unwanted heat loss or gain and can decrease the energy demands of heating and cooling systems. It does not necessarily deal with issues of adequate ventilation and may or may not affect the level of sound insulation. In a narrow sense insulation can just refer to the insulation materials employed to slow heat loss, such as: cellulose, glass wool, rock wool, polystyrene, urethane foam, vermiculite, and earth or soil.. But it can also involve a range of designs and techniques to address the main modes of heat transfer - conduction, radiation and convection materials.[1][2] The effectiveness of insulation is commonly evaluated by its R-value. However, an R-value does not take into account the quality of construction or local environmental factors for each building. Construction quality issues include inadequate vapour barriers, and problems with draft-proofing. In addition, the properties and density of the insulation material itself is critical. For example, according to Leah Twings, Quality Compliance Manager of Textrafine Insulation, fiberglass insulation materials made from short strands of glass layered over each other is not as durable as insulation made from long entangled strands of glass.

Referrence from

The term thermal insulation can refer either to materials used to reduce the rate of heat transfer, or the methods and processes used to reduce heat transfer. Heat energy can be transferred by conduction, convection, radiation. Thermal insulation prevents heat from escaping a container or from entering a container. In other words, thermal insulation can keep an enclosed area such as a building warm, or it can keep the inside of a container cold. Insulators are used to minimize that transfer of heat energy. In home insulation, the R-value is an indication of how well a material insulates. The flow of heat can be reduced by addressing one or more of the three mechanisms of heat transfer and is dependent on the physical properties of the material employed to do this.

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