Building insulation is any object in a building. While the majority of insulations are for thermal purposes, the term also applies to acoustical insulation, fire insulation, and impact insulation (eg 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 in buildings is an important factor in achieving thermal comfort for its occupants. Insulation reduces unwanted heat loss and increases the efficiency of heating and cooling systems. It does not really have any impact on the issue of ventilation. Cellulose fiber, wool, polystyrene, urethane foam, vermiculite, perlite, wood fiber, fiber plant (cannabis, flax, cotton, cork, etc.), recycled cotton denim, plant straw, animal fiber (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 main modes of heat transfer – conduction, radiation and convection materials. Many of the materials in this list of heat conduction and convection by the simple expedient of trapping large amounts of air (or other gas) in a way that results in a material that employs the low thermal conductivity of small pockets of gas, rather than the much higher conductivity of typical solids. A similar gas-trap is used in animal hair, down feathers, and in air-containing insulating fabrics. The effectiveness of Reflective Insulation (Radiant Barrier) is discussed by the Reflectivity (Emittance) of the surface with airspace facing the heat source. The effectiveness of bulk insulation is evaluated by its R – value, of which there are two – metric (US) 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). 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 materials is critical.
How much does it cost to have a building, 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 in the context of the energy transfer and the direction of the movement. This may change during the day and 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 to your home and where you are. A qualified home energy auditor will include an audit check as a routine part of a whole-house energy audit. However, you can sometimes perform self-assessment in certain areas of the home, such as attics. Here, a visual inspection, with the help of a ruler, can give you a sense of whether you can benefit from additional insulation. An initial estimate of insulation needs in the United States can be determined by the US Department of Energy’s ZIP code insulation calculator.
In Russia, the availability of abundant and poorly insulated, overheated and inefficient consumption of energy. The Russian Center for Energy Efficiency found that Russian buildings are either over- or under-heated, and often consume up to 50 percent more heat and hot water than needed. 53 percent of all carbon dioxide (CO 2) emissions in Russia are produced by heating and generating electricity for buildings. However, greenhouse gas emissions from the Soviet bloc are still below their 1990 levels.
In cold conditions, the main aim is to reduce heat flow out of the building. The components of the building envelope – windows, doors, roofs, walls, and air infiltration barriers – are all important sources of heat loss; in an otherwise well insulated home, an important source of heat transfer. R-value of about 0.17 m 2 K o / W (compared to 2-4 m 2 K o / W for glass wool batts). Losses can be reduced by good weatherization, bulk insulation, and minimizing the amount of non-insulative (particularly non-solar facing) glazing. Indoor thermal radiation can also be a disadvantage with spectrally selective (low-e, low-emissivity) glazing. Some insulated glazing systems can double to triple R values.
In hot conditions, the greatest source of heat energy is solar radiation. This method can be used to increase the temperature of the environment by increasing the temperature of the environment. The Solar Heat Gain Co-efficient (SHGC) of standard single glazing can be around 78-85%. Can be reduced by adequate shading from the sun, light colored roofing, spectrally selective (heat-reflective) paints and coatings and various types of insulation for the rest of the envelope. Specially coated glazing can reduce SHGC to around 10%. Radiant barriers are highly effective for attic spaces in hot climates. In this application, they are much more effective in hot climates than cold climates. For downward heat flow, convection is weak and radiation dominates heat transfer across an air space. Radiant barriers must be adequate. If refrigerative air-conditioning is employed in a hot, humid climate, then it is particularly important to seal the building envelope. Dehumidification of humid air infiltration can waste significant energy. On the other hand, some building designs are based on effective cross-ventilation instead of refrigerating air-conditioning to provide convective cooling from prevailing breezes.
Optimal placement of building elements (eg windows, doors, heaters) can play a significant role in the insulation of solar panels. Reflective laminates can help reduce passive solar heat in pole barns, garages, and metal buildings.
See insulated glass for discussion of windows.
The thermal envelope defines the conditioned or living space in a house. The attic gold base may or may not be included in this area. Reducing airflow from inside to outside can help to reduce convective heat transfer significantly. Ensuring low convective heat transfer also requires attention to building construction (weatherization) and the correct installation of insulative materials. The less natural airflow into a building, the more mechanical ventilation will be required to support human comfort. High humidity can be a significant issue associated with lack of airflow, causing condensation, rotting construction materials, and encouraging microbial growth such as molds and bacteria. Moisture can also drastically reduce the effectiveness of a thermal bridge (see below).
Thermal bridges are points in the building that allow heat conduction to occur. Since heat flows through the path of least resistance, thermal bridges can contribute to poor energy performance. A thermal bridge is created when a temperature difference is not changed, in which the heat flow is not interrupted by thermal insulation. Common building materials that are poor insulators include glass and metal. A building design may have limited capacity for insulation in some areas of the structure. A common construction design is based on studs, in which thermal bridges are common in wood or steel studs and joists, which are typically fastened to metal. Notable areas that are most commonly lacking and areas where insulation, equipment and electrical equipment (outlets and light switches), plumbing, fire alarm equipment, etc.Thermal bridges can also be created by uncoordinated construction, for example by closing off parts of external walls before they are fully insulated. The existence of inaccessible voids within the wall which can be devoid of thermal bridging. Some forms of insulation and heat transfer are more likely to occur in this state of the art. The heat conduction can be minimized by any of the following: reducing the cross sectional area of the bridges, increasing the bridge length, or decreasing the number of thermal bridges. One method of reducing thermal bridge is the installation of an insulation board (eg EPS XPS foam board, wood fiber board, etc.) over the exterior outside wall. Another method is using insulated lumber framing for a thermal break inside the wall.
Insulating buildings is much easier than retrofitting, and it is more often than not.
There are two types of building insulation – bulk insulation and reflective insulation. Most buildings use a combination of both types to make up a total building insulation system. The type of insulation is one of the three types of heat transfer – conduction, convection, and radiation.
Bulk insulators conductive heat transfer and convective block. The denser material is the best it will conduct heat. Because air has such a low density, is a very poor conductor and therefore makes a good insulator. Insulation to resist conductive heat transfer uses air spaces between fibers, inside foam or plastic bubbles and cavities like attic. This is beneficial in an excited or cooled building, but can be a liability in a passively cooled building; adequate provisions for cooling by ventilation or radiation are needed.
Radiant barriers in the air space. Radiant gold reflective insulation Radiant barriers are often seen in a downward direction, because of the tendency to be dominated by convection. This means that for attics, ceilings, and roofs, they are most effective in hot climates. They also have a role in reducing heat losses in cool climates. However, much more can be achieved through the addition of bulk insulators (see above). Some radiant barriers are spectrally selective and will preferentially reduce the flow of infra-red radiation in comparison to other wavelengths. For instance low-emissivity (low-e) windows will transmit light and short-wave infra-red energy into a building purpose the long-wave infrared radiation generated by interior furnishings. Similarly, special heat-reflective paints are able to reflect more heat than visible light, or vice versa. Thermal emissivity probably best reflects the effectiveness of radiant barriers. Some manufacturers quote an ‘equivalent’ R-value for these products the net result (radiation, conduction, convection). A film of dirt or moisture can alter the emissivity and hence the performance of radiant barriers.
Eco-friendly insulation is a term used for insulating products with limited environmental impact. The use of a life-cycle assessment (LCA). A number of studies compared the environmental impact of insulation materials in their application. The comparison shows that the most important is the insulation value of the product meeting the technical requirements for the application. Only in a second order step. The report commissioned by the Belgian government to VITO is a good example of such a study. A valuable way to graphically represent such results by a spider diagram.