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Insulating Materials
This is a list of insulation materials used around the world. Typical R-values are given for various materials and structures as approximations based on the average of available figures and are sorted by lowest value.'' R-value at 1 m'' gives R-values normalised to a thickness and sorts by median The median of a set of numbers is the value separating the higher half from the lower half of a Sample (statistics), data sample, a statistical population, population, or a probability distribution. For a data set, it may be thought of as the “ ... value of the range. References {{Reflist Building insulation materials ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Median
The median of a set of numbers is the value separating the higher half from the lower half of a Sample (statistics), data sample, a statistical population, population, or a probability distribution. For a data set, it may be thought of as the “middle" value. The basic feature of the median in describing data compared to the Arithmetic mean, mean (often simply described as the "average") is that it is not Skewness, skewed by a small proportion of extremely large or small values, and therefore provides a better representation of the center. Median income, for example, may be a better way to describe the center of the income distribution because increases in the largest incomes alone have no effect on the median. For this reason, the median is of central importance in robust statistics. Median is a 2-quantile; it is the value that partitions a set into two equal parts. Finite set of numbers The median of a finite list of numbers is the "middle" number, when those numbers are liste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Building Insulation Materials
Building insulation materials are the building materials that form the thermal envelope of a building or otherwise reduce heat transfer. Insulation may be categorized by its composition (natural or synthetic materials), form (batts, blankets, loose-fill, spray foam, and panels), structural contribution (insulating concrete forms, structured panels, and straw bales), functional mode (conductive, radiative, convective), R-value (insulation), resistance to heat transfer, environmental impacts, and more. Sometimes a thermally reflective surface called a radiant barrier is added to a material to reduce the transfer of heat through radiation as well as conduction. The choice of which material or combination of materials is used depends on a wide variety of factors. Some insulation materials have health risks, some so significant the materials are no longer allowed to be used but remain in use in some older buildings such as asbestos fibers and Urea-formaldehyde#Foam insulation, urea. C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardwood
Hardwood is wood from Flowering plant, angiosperm trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal ecosystem, boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes from angiosperm trees) contrasts with softwood (which is from gymnosperm trees). Characteristics Hardwoods are produced by Flowering plant, angiosperm trees that reproduce by flowers, and have broad leaves. Many species are deciduous. Those of temperate regions lose their leaves every autumn as temperatures fall and are dormant in the winter, but those of tropical regions may shed their leaves in response to seasonal or sporadic periods of drought. Hardwood from deciduous species, such as oak, normally shows annual dendrochronology, growth rings, but these may be absent in some tropical timber, tropical hardwoods. Hardwoods have a more complex structure than softwoods and are often much slower growing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood Chips
Woodchips are small- to medium-sized pieces of wood formed by cutting or chipping larger pieces of wood such as trees, branches, logging residues, stumps, roots, and wood waste. Woodchips may be used as a biomass solid fuel and are raw material for producing wood pulp. They may also be used as an organic mulch in gardening, landscaping, and ecosystem restoration; in bioreactors for denitrification; and as a substrate for mushroom cultivation. The process of making woodchips is called wood chipping and is done using a wood chipper. The types of woodchips formed following chipping is dependent on the type of wood chipper used and the material from which they are made. Woodchip varieties include: forest chips (from forested areas), wood residue chips (from untreated wood residues, recycled wood and off-cuts), sawing residue chips (from sawmill residues), and short rotation forestry chips (from energy crops). Raw materials The raw materials of woodchips can be pulpwood, waste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Softwood
Scots pine, a typical and well-known softwood Softwood is wood from gymnosperm trees such as conifers. The term is opposed to hardwood, which is the wood from angiosperm trees. The main differences between hardwoods and softwoods is that the softwoods completely lack vessels (pores). The main softwood species (pines, spruces, larches, false tsugas) also have resin canals (or ducts) in their structure. Characteristics Softwood is wood from gymnosperm trees such as pines and spruces. Softwoods are not necessarily softer than hardwoods. The hardest hardwoods are much harder than any softwood, but in both groups there is enormous variation with the range of wood hardness of the two groups overlapping. For example, balsa wood, which is a hardwood, is softer than most softwoods, whereas the longleaf pine, Douglas fir, and yew softwoods are much harder than several hardwoods. Several specific natural, macroscopic and microscopic features of wood are used in the identification p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papercrete
Papercrete is a building material that consists of re-pulped paper fiber combined with Portland cement or clay, as well as other soils. First patented in 1928 by Eric Patterson and Mike McCain (who originally named it "padobe" and "fibrous cement"), it was revived during the 1980s. It is generally perceived as an environmentally friendly material due to the significant recycled content, although this is offset by the presence of cement, which emits CO2 during manufacture. The material also lacks standardisation, and proper use therefore requires care and experience. However the inventors have both contributed considerably to research into developing the necessary machinery to make it, as well as methods of using it for construction. Manufacture The paper used in papercrete can come from a variety of sources, including newspaper, junk mail, magazines, books. A mixer is used to pulp the mix before this is combined with cement or clay. Depending on the type of mixer, the paper may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Straw-bale Construction
Straw-bale construction is a building method that uses bales of straw (usually wheatAsdrubali, F., D’Alessandro, F., Schiavoni, S.: A review of unconventional sustainable building insulation materials. Sustain Mater Technol. 4, 1–17 (2015). https://doi.org/10.1016/j.susmat.2015.05.002 straw) as structural elements, building insulation, or both. This construction method is commonly used in natural building or "brown" construction projects. Research has shown that straw-bale construction is a sustainable method for building, from the standpoint of both materials and energy needed for heating and cooling. Advantages of straw-bale construction over conventional building systems include the renewable nature of straw, cost, easy availability, naturally fire-retardant and high insulation value. Disadvantages include susceptibility to rot, difficulty of obtaining insurance coverage, and high space requirements for the straw itself. Research has been done using moisture probes placed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermiculite
Vermiculite is a hydrous phyllosilicate mineral which undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently; commercial furnaces can routinely produce this effect. Vermiculite forms by the weathering or hydrothermal alteration of biotite or phlogopite. http://www.mindat.org/min-4170.html Mindat.org Large commercial vermiculite mines exist in the United States, Russia, South Africa, China, and Brazil. Occurrence Vermiculite was first described in 1824 for an occurrence in Millbury, Massachusetts. Its name is from the Latin , "to breed worms", for the manner in which it exfoliates when heated. It typically occurs as an alteration product at the contact between felsic and mafic or ultramafic rocks such as pyroxenites and dunites. It also occurs in carbonatites and metamorphosed magnesium-rich limestone. Associated mineral phases include: corundum, apatite, serpentine, and talc. It occurs interlayered with chlorite, biotite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perlite
Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the Hydrate, hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently. It is an industrial minerals, industrial mineral, suitable "as ceramic flux to lower the sintering temperature", and a commercial product useful for its low density after processing. Properties Perlite softens when it reaches temperatures of . Water trapped in the structure of the material vaporises and escapes, and this causes the expansion of the material to 7–16 times its original volume. The expanded material is a brilliant white, due to the reflectivity of the trapped bubbles. Unexpanded ("raw") perlite has a bulk density around 1100 kg/m3 (1.1 g/cm3), while typical expanded perlite has a bulk density of about 30–150 kg/m3 (0.03–0.150 g/cm3). Typical analysis *70–75% silicon dioxide: SiO2 *12–15% aluminium oxide: Al2O3 *3–4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementitious Foam
Cementitious foam insulation is a cement-based thermal and acoustic insulation, with an R-value similar to that of fiberglass. It is installed as a foam with a consistency like shaving cream, or as pre-cast slabs. The current cost is similar to that of polyurethane foams. Unlike many foam-in-place polyurethane foams, it is nonflammable and non-toxic. As it is water-based, it offgasses water vapour while curing, requiring ventilation and in some cases a dehumidifier. It cures more slowly than organic foams. However, it does not offgas volatile organic compounds Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. They are common and exist in a variety of settings and products, not limited to house mold, upholstered furniture, arts and crafts sup ... as many organic foams do. Like cement, it is water-soluble until cured, but after curing it is water-resistant, but water-permeable. It does not expand on setting, but may shr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, cups, jars, etc.). , over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. Many kinds of polyethylene are known, with most having the chemical formula (C2H4)''n''. PE is usually a mixture of similar polymers of ethylene, with various values of ''n''. It can be ''low-density'' or ''high-density'' and many variations thereof. Its properties can be modified further by crosslinking or copolymerization. All forms are nontoxic as well as chemically resilient, contributing to polyethylene's popularity as a multi-use plastic. However, polyethylene's chemical resilience also makes it a long-lived and decomposition-resistant pollutant when disposed of improperly. Being a h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral Wool
Mineral wool is any fibrous material formed by spinning or drawing molten mineral or rock materials such as slag and ceramics. Applications of mineral wool include thermal insulation (as both structural insulation and pipe insulation), filtration, soundproofing, and hydroponic growth medium. Naming Mineral wool is also known as rock wool, mineral cotton, mineral fiber, man-made mineral fiber (MMMF), and man-made vitreous fiber (MMVF). Specific mineral wool products are stone wool and slag wool. Europe also includes glass wool which, together with ceramic fiber, are entirely artificial fibers that can be made into different shapes and are spiky to touch. History Slag wool was first made in 1840 in Wales by Edward Parry, "but no effort appears to have been made to confine the wool after production; consequently it floated about the works with the slightest breeze, and became so injurious to the men that the process had to be abandoned". A method of making mineral wool ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
