Thermal insulation keeps heat in and cold out – it’s the material in your insulated coffee cup or fire-resistant clothing. It is also the stuff in your house’s attic, and it helps make homes energy efficient.
The key characteristics of thermal Insulation Perth are Vapour Permeability and Thermal Resistance. Other factors to consider are Compression Resistance and Fire Retardancy.
Loose Fill
Loose fill insulation is an easy-to-install thermal insulation product that comes in a variety of densities. It can be blown into enclosed cavities such as wall spaces, or unenclosed areas such as attics. It is made from a combination of recycled paper, newspaper, or cardboard and cellulose fibers. It is typically manufactured locally, which makes it a cost-effective choice for DOE funded low income weatherization projects. It also does a good job of slowing air movement and is a good fire retardant. It poses less of an inhalation hazard than fiberglass, and it doesn’t contain any volatile organic compounds.
Some loose-fill insulations have been known to irritate the skin and respiratory system. It is also worth noting that cellulose can smolder under certain conditions, so it should not be installed in wall cores around recessed lights and electrical boxes, as well as near furnace and wood stove chimneys. It is important to note that the insulator should provide details about the R-value of their product at its settled density. This information is often included in the UL listing for the insulation and should be available from the manufacturer.
The best loose-fill cellulose insulation is borate stabilized, which helps to reduce the risk of health problems. It can be used in walls that were insulated with fiberglass batts, although it is often recommended to remove them first. Skilled cellulose professionals can snake a fill tube into an existing fiberglass cavity, crushing the batts and achieving a full uniform application of new cellulose insulation.
It is possible to use loose-fill cellulose in concrete block walls, and it has been shown to improve 2 hour fire ratings to four hours. This type of insulation is often specified for concrete wall retrofits in the state of Massachusetts.
Another type of loose-fill masonry insulation is perlite. It is an inorganic mineral that is essentially as permanent as the walls it insulates, and it is also cost-effective. It is lightweight, pours easily and quickly, and doesn’t require special equipment or skills to install.
It is important to note that any type of loose-fill insulation may contain asbestos, and it is therefore necessary to have an asbestos survey conducted before proceeding with installation. If asbestos is found, it should be professionally removed before insulating the home. It is important to understand that asbestos cannot be detected by any non-invasive test, and only an asbestos survey can accurately determine whether or not asbestos has been used in a home. It is advisable to hire an experienced asbestos surveyor who can safely locate and remove all potential sources of asbestos.
Mineral Fibre
Mineral fibre is a broad term that covers several types of insulation, including rock wool and slag wool. It is created by melting naturally-occurring minerals such as stone, basalt, or iron ore slag in a high-temperature furnace. The result is a wool-like material that is very flexible and has good thermal and acoustic properties. It can be used in both metal and wood frame construction. It is water-repellent, but vapor-permeable, and therefore can be used in outdoor applications as long as it is protected with a metal jacket.
Because it is made from recycled materials, slag wool has an excellent environmental footprint. It is typically sourced from industrial waste, and it is often blended with steel or iron oxide to reduce the embodied energy of production. The slag is also melted in a single melt process, which makes it more efficient than other mineral wool products that are blown into place through a nozzle.
Another type of mineral fiber is glass wool, which is produced by heating borosilicate glass at high temperatures and then drawing it through rotating nozzles. This creates a fine, spun-like fiber that has similar characteristics to rock wool, but it is more durable and offers excellent fire resistance. This product is available in a variety of mats, boards, and blankets.
Cellulose insulation is another form of mineral fiber that is commonly used in residential and commercial buildings. It is made from recycled paper, primarily newsprint and has a high recycled content (typically 82% to 85%). It is treated with the chemical borate to make it resistant to pests and fire.
Other forms of mineral fiber include cotton and linen. These products are lightweight, but still provide excellent acoustic and thermal performance. They are also naturally insect and rodent-resistant.
In addition to their use in building and construction, these textiles have been incorporated into clothing, gear, sportswear and other products. In the future, it is likely that more athleisure brands will incorporate these fibres to add warmth without adding bulk or to help regulate body temperature and reduce sweating.
Plant/Animal Derived
In the context of global climate change and high energy consumption, the development of new materials with lower embodied energies is an urgent matter. Reusing industrial and agricultural by-products is a crucial solution to reduce energy usage. The use of natural, renewable materials in building construction is one such way to do so. This is especially true for the insulating materials in buildings.
In this regard, there is a range of possibilities:
Plant-derived thermal insulation has been used for years, and it has proven to be a successful insulator. It is also highly sustainable, and it can be made from a number of plant and animal sources. These include cellulose fibre, sheep wool, cotton and flax. These products are made from natural raw materials with low embodied energy, and can be fabricated into batts or compressed board. They can also be recycled and reused at the end of their service life.
Several research projects have also led to the production of innovative natural insulating materials. For example, a carding-folding process has been used to produce composite products that combine natural fibres of animal origin with PET and recycled polyester (rPET/rPES). The resulting thermal insulation products have good hygrothermal properties, and they can be combined with other building components in order to achieve optimum performance.
There are also a number of other plant and animal-based insulating materials that can be used to provide thermal insulation. These include cellulose fibre derived from wheat straw, barley straw and rye, hemp, cotton and flax. In addition, there are a variety of animal-derived insulating materials including goose or duck feathers (preferably from animals that have been raised humanely rather than slaughtered), milkweed seed pod fibres and kapok fibres (from the seeds of tropical trees).
These insulation materials have a positive impact on the quality of the indoor air in terms of moisture regulation. They are also a source of natural fibres, which are not harmful to humans and do not release irritating substances when they decompose. Moreover, these insulation materials have a high resistance to biological attack by worms and insects. This is important because it means that they can be safely used in living environments without any concerns regarding pest infestations.
Cellular Plastic
In contrast to loose fill and mineral fibre insulation, cellular plastic insulation has a dense internal structure. This is due to a process of cellular foaming. The base material is a solid thermoplastic resin such as polyurethane, polystyrene, phenolic or polyvinyl chloride. A blowing agent is absorbed or dissolved within the solid material, and then subjected to high temperatures. This causes the dissolved gas molecules to diffuse and nucleate, creating a cellular foam. The average cellular size of the resultant material depends upon the type of base plastic, the type of foaming system and the conditions under which the foaming takes place.
Cellular plastic insulations are available in a wide range of sizes, densities and colour options. They are produced as slabs, blocks, sheets, films, molded shapes and sprayed coatings. They offer a wide variety of physical, mechanical and electrical insulating properties which depend on the density, cellular size, and other characteristics.
Typically, these materials are oil-derived and come in the form of rigid polyurethane, phenolic or extruded polystyrene sheeting and spray foam. This means they are long lasting, do not require protection from moisture or vermin infestation and can be easily installed. The product is also non-toxic and non-combustible.
The thermal efficiency of a cellular plastic insulator is determined by the average heat conductivity (k value) of the individual cells. As the insulator ages, its k value degrades. This may be due to replacement of the cellular material with different gases or moisture, changes in the cell size, penetration of water or air, degradation of the solid face by ultraviolet light and atmospheric oxygen, and a combination of these effects.
These aging effects will increase the thermal conductivity of the insulator, decreasing its effective k value and making it less effective. For this reason, it is important to select a product with an extended service life and a good warranty.