Building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation (e.g. for vibrations caused by industrial applications). Often an insulation material will be chosen for its ability to perform several of these functions at once.
Thermal 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, perlite, wood fibre, plant fibre (cannabis, flax, cotton, cork, etc.), recycled cotton denim, plant straw, animal fibre (sheep's wool), cement, and earth or soil, Reflective Insulation (also known as Radiant Barrier) 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 Reflective Insulation (Radiant Barrier) is commonly evaluated by the Reflectivity (Emittance) of the surface with airspace facing to the heat source.
The effectiveness of bulk insulation is commonly evaluated by its R-value, of which there are two - metric (SI) and US customary, the former being 0.176 times the latter. For attics, it is recommended that it should be at least R-38 (US customary, R-6.7 metric).[3] 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 vapor barriers, and problems with draft-proofing. In addition, the properties and density of the insulation material itself is critical.
Planning
How much insulation a house should have depends on building design, climate, energy costs, budget, and personal preference. Regional climates make for different requirements. Building codes specify only the bare minimum; insulating beyond what the code requires is often recommended.
The insulation strategy of a building needs to be based on a careful consideration of the mode of energy transfer and the direction and intensity in which it moves. This may alter throughout the day and from season to season. It is important to choose an appropriate design, the correct combination of materials and building techniques to suit the particular situation.
To determine whether you should add insulation, you first need to find out how much insulation you already have in your home and where. A qualified home energy auditor will include an insulation check as a routine part of a whole-house energy audit.[4]
In the USA
An initial estimate of insulation needs in the United States can be determined by the US Department of Energy's ZIP code insulation calculator.
Russia
In Russia the luxury of cheap gas has led to poorly insulated, overheated and inefficient consumers of energy. The Russian Center for Energy Efficiency found that Russian buildings are either over- or under-heated, often consume up to 50 percent more heat and hot water than needed. Fifty-three percent of all carbon dioxide (CO2) emissions in Russia are produced through heating and generating electricity for buildings.[5] However, Green House Gas (GHG) emissions from the Soviet Bloc are still below their 1990 levels).[citation needed]
Thermal 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, perlite, wood fibre, plant fibre (cannabis, flax, cotton, cork, etc.), recycled cotton denim, plant straw, animal fibre (sheep's wool), cement, and earth or soil, Reflective Insulation (also known as Radiant Barrier) 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 Reflective Insulation (Radiant Barrier) is commonly evaluated by the Reflectivity (Emittance) of the surface with airspace facing to the heat source.
The effectiveness of bulk insulation is commonly evaluated by its R-value, of which there are two - metric (SI) and US customary, the former being 0.176 times the latter. For attics, it is recommended that it should be at least R-38 (US customary, R-6.7 metric).[3] 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 vapor barriers, and problems with draft-proofing. In addition, the properties and density of the insulation material itself is critical.
Planning
How much insulation a house should have depends on building design, climate, energy costs, budget, and personal preference. Regional climates make for different requirements. Building codes specify only the bare minimum; insulating beyond what the code requires is often recommended.
The insulation strategy of a building needs to be based on a careful consideration of the mode of energy transfer and the direction and intensity in which it moves. This may alter throughout the day and from season to season. It is important to choose an appropriate design, the correct combination of materials and building techniques to suit the particular situation.
To determine whether you should add insulation, you first need to find out how much insulation you already have in your home and where. A qualified home energy auditor will include an insulation check as a routine part of a whole-house energy audit.[4]
In the USA
An initial estimate of insulation needs in the United States can be determined by the US Department of Energy's ZIP code insulation calculator.
Russia
In Russia the luxury of cheap gas has led to poorly insulated, overheated and inefficient consumers of energy. The Russian Center for Energy Efficiency found that Russian buildings are either over- or under-heated, often consume up to 50 percent more heat and hot water than needed. Fifty-three percent of all carbon dioxide (CO2) emissions in Russia are produced through heating and generating electricity for buildings.[5] However, Green House Gas (GHG) emissions from the Soviet Bloc are still below their 1990 levels).[citation needed]
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